There have been two fatalities after a series of huge earthquakes overnight, Prime Minister John Key says.
Authorities were scrambling this morning to assess damage and respond to reports of injuries after the first 7.5 magnitude earthquake centred near Hanmer Springs.
Watch: Prime Minister John Key media conference
The Ministry of Civil Defence and Emergency Management confirmed there had been two deaths from the earthquake.
One person died in a house that collapsed in Kaikoura, and a second person died at a house in Mt Lyford, north of Christchurch.
Mr Key said a Defence Force helicopter would be flying to Kaikoura and another one would be available in Wellington.
An Urban Search and Rescue team from Christchurch was also on its way to Kaikoura by helicopter, along with two further assessment teams deployed to Waiau and Blenheim.
As a result of the quake, Mr Key cancelled his proposed trade trip to Argentina, and will decide later this week whether to attend APEC in Peru next weekend.
Nelson Marlborough District Health Board said five people had been admitted to Wairau Hospital by early this morning with various injuries, some described as moderate.
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The first quake struck at 12.02am, near Hanmer Springs, at a depth of 16km. It was followed by a series of large earthquakes across New Zealand up to 6.2 in magnitude, which prompted tsunami alerts, causing residents of coastal areas to flee inland.
GNS science said there had been at least 250 aftershocks since the massive shake just after midnight, with more than 30 of them above magnitude 5, and three of magnitude 6 and above.
Most were in the upper South Island, in Seddon and Kaikoura, but a 4.9 magnitude earthquake hit Paraparaumu and a 4.9 hit Wellington in the early hours.
The Civil Defence ministry said roads were closed on State Highway 1 between Blenheim and Picton, State Highway 6 between between Blenheim and Nelson, and State Highway 7 between Springs Junction and Waipara.
It warned people to check for any dangers on damaged properties including to gas and water supplies.
The earthquake sequence is the biggest since the 5.7 Valentine's Day earthquake, which caused cliffs in the Christchurch suburb of Sumner to fall and liquefaction in some east Christchurch areas.
Marlborough civil defence controller Richard McNamara with a map of the Ure River area. Photo: RNZ / Kate Newton
A landslide triggered by the November 14 earthquake covers State Highway 1 south of Kaikoura. Photo: AFP
Quake damage to SH1. Photo: AFP
The view from inside one of the blocked road tunnels on SH1 near Kaikoura. Photo: AFP
Quake damage to SH1. Photo: AFP
Emergency services officers inspect the damage caused to Rotherham Road near Waiau town. Photo: AFP
Quake damage to SH1. Photo: AFP
Quake damage to SH1. Photo: AFP
A damaged home in Waiau. Photo: AFP
French tourists Lucie and Louisa moments before leaving Kaikoura on the HMNZS Canterbury on Wednesday. Photo: RNZ / Max Towle
Part of the Kēkerengū fault in Marlborough. Photo: RNZ / Alex Perrottet
Damage along the Kēkerengū fault in Marlborough. Photo: RNZ / Alex Perrottet
Quake damage in Ward. Photo: RNZ / Kate Newton
Mt Lyford resident Don McIntosh's cars were shunted around by the earthquake. Photo: RNZ / Conan Young
A helicopter lowers itself to land to collect luggage of evacuees heading to the HMNZS Canterbury. Photo: RNZ / Claire Eastham-Farrelly
A helicopter ferries evacuees luggage onto the HMNZS Canterbury. Photo: RNZ / Claire Eastham-Farrelly
RNZAF's Hercules airdrops water to Kaikoura. Photo: RNZ / Maja Burry
RNZAF's Hercules airdrops water to Kaikoura. Photo: RNZ / Maja Burry
The Clarence rafters. Photo: Deirdre Lusby
The Clarence rafters were evacuated by helicopter from Muzzle Station. Photo: Deirdre Lusby
The airforce helicopter flies in to Kaikoura to drop off supplies and pick up those still stuck in Kaikoura. Photo: RNZ / Maja Burry
Boat taking evacuees to HMNZS. Photo: RNZ / Rebekah Parsons-King
John Key talks to tourists waiting to leave. Photo: RNZ / Rebekah Parsons-King
John Key in Kaikoura. Photo: RNZ / Rebekah Parsons-King
People waiting for buses to HMNZS. Photo: RNZ / Rebekah Parsons-King
Sarah, baby Kenoah and Tom Herrmann, from Germany, are not leaving Kaikoura yet. Photo: RNZ / Rebekah Parsons-King
Boats come back from HMNZS. Photo: RNZ / Rebekah Parsons-King
People being transported to HMNZS. Photo: RNZ / Rebekah Parsons-King
Another load of people are transported to HMNZS. Photo: RNZ / Rebekah Parsons-King
Road damage in Kaikoura. Photo: RNZ / Rebekah Parsons-King
Damage to highways near Kaikoura following the quake. Photo: RNZ / Simon Morton
Damage to highways near Kaikoura. Photo: RNZ / Simon Morton
Simon Morton investigates raised seabeds near Kaikoura. Photo: RNZ / Simon Morton
Damage in the Kaikoura area following Monday's earthquake. Photo: RNZ / Simon Morton
Damage seen near Ohau. Photo: RNZ / Simon Morton
Repair work on quake damage to buildings in central Wellington is well underway. Photo: RNZ / Aaron Smale
Repair work on quake damage to buildings in central Wellington is well underway. Photo: RNZ / Aaron Smale
Quake damage in central Wellington. Photo: RNZ / Aaron Smale
Marlborough district council building inspector Cherie Newman fills out a yellow restricted access placard for a badly damaged house in Ward, south Marlborough. Photo: RNZ / Kate Newton
Transport Minister Simon Bridges in Kaikoura today. Photo: RNZ / Rebekah Parsons-King
Prime Minister John Key talks to local Fire Service personnel in his second visit to Kaikoura since the quake overnight Sunday. Photo: RNZ / Rebekah Parsons-King
John Key talks to Kaikoura business owners in his second visit to the town since the big quake. Photo: RNZ / Rebekah Parsons-King
Kaikoura business owners. Photo: RNZ / Rebekah Parsons-King
Tourists in Kaikoura queue to be taken to the navy ship off the coast of the quake-hit town. Photo: RNZ / Rebekah Parsons-King
Tourists being taken by bus from Kaikoura to where they can board a navy ship. Photo: RNZ / Rebekah Parsons-King
Tourists being taken by bus from Kaikoura to where they can board a navy ship. Photo: RNZ / Rebekah Parsons-King
Ward resident Kerry Snell and Red Cross volunteer Ian George assess a fallen water tank on Mr Snell's property. Photo: RNZ / Kate Newton
HMNZS staff waiting on chopper with supplies for Kaikoura. Photo: RNZ/Rebekah Parsons-King
Navy staff waiting on chopper with supplies for Kaikoura. Photo: RNZ/Rebekah Parsons-King
Lieutenant Commander Matt Kaio arrives in Kaikoura from HMNZS Wellington. Photo: RNZ/Rebekah Parsons-King
Staff Sergeant Simon Haughey, beach master for the evacuation, and Nicole Booth, lcws, in Kaikoura, cut off after the 7.5 magnitude earthquake that struck near Hanmer Springs. Photo: RNZ / Rebekah Parsons-King
HMNZS Canterbury arrives in Kaikoura. Photo:
RNZ/Rebekah Parsons-King
HMNZS Canterbury arrives in Kaikoura, after the town was cut-off following the 7.5 magnitude earthquake near Hanmer Springs. Photo: RNZ / Rebekah Parsons-King
HMNZS Canterbury arrives in Kaikoura, which has been cut-off since the 7.5 magnitude earthquake struck near Hanmer Springs. Photo: RNZ / Rebekah Parsons-King
The police cordon around the quake-damaged buildings. Photo: RNZ / Emile Donovan
The cordon around quake-damaged Wellington buildings. Photo: RNZ / Emile Donovan
The cordon around Pipitea House. Photo: RNZ / Emile Donovan
The cordon around Pipitea House. Photo: RNZ / Emile Donovan
A cordon in place in central Wellington. Photo: RNZ / Emile Donovan
Earthquake damage at the Waiau Hotel. Photo:
AFP
Authorities have closed Molesworth St in central Wellington because of potential building facade collapse. Photo: RNZ / Alex Perrottet
The closed building on Molesworth St, Wellington. Photo: Mei Heron / RNZ
Fire and police officers were expected to be working through the night. Photo: RNZ / Mei Heron
Red Cross helping earthquake-stranded. Photo: Corinne Eambler / Red Cross
Waiau School has become a welfare centre for the earthquake-hit North Canterbury township. Photo: RNZ / Conan Young
Kaikoura resident Mark Solomon showed us around his home that was badly damaged in the quake. Photo: RNZ / Rebekah Parsons-King
Damage at Mark Solomon's property. Photo: RNZ / Rebekah Parsons-King
Eruera and Mark Solomon. Photo: RNZ / Rebekah Parsons-King
Mark Solomon's family home of 16 people was badly damaged in the quake. Photo: RNZ / Rebekah Parsons-King
The kitchen contents emptied onto the floor. Photo: RNZ / Rebekah Parsons-King
Eruera Solomon, Mark Solomon's 15 year old son does not want to return to the family home. Photo: RNZ / Rebekah Parsons-King
Power lines down in Kaikoura. Photo: RNZ / Rebekah Parsons-King
Power lines down in Kaikoura. Photo: RNZ / Rebekah Parsons-King
The 4Square is closed as are most businesses. Photo: RNZ / Rebekah Parsons-King
NZ Defence Force brings supplies. Photo: RNZ / Rebekah Parsons-King
The facade of Mitre 10 fell in the earthquake.Photo: RNZ / Rebekah Parsons-King
Lines of people line up outside of New World in Kaikoura. Photo: RNZ / Rebekah Parsons-King
Takahanga Marae feeding the masses of stranded tourists. Photo: RNZ / Rebekah Parsons-King
Hundreds of people have waited for flights out of Kaikoura at the rugby club rooms. Photo: RNZ / Rebekah Parsons-King
Fire crew inspect buidlings along the main street in Kaikoura. Photo: RNZ / Rebekah Parsons-King
The 4Square on the main road in Kaikoura remains closed. Photo: RNZ / Rebekah Parsons-King
A Westpac ATM is out of order. Photo: RNZ / Rebekah Parsons-King
Chinese tourists Xiaolei Chen and Jiangyong are honeymooning in New Zealand. They were evacuated by the Chinese consulate. Photo: RNZ / Rebekah Parsons-King
People wait at the rugby club to be airlifted out. Photo: RNZ / Rebekah Parsons-King
Ward local Di Litchfield at the emergency welfare centre. Photo: RNZ / Kate Newton
Koko Lambert with her daughter Tiara, 7, and son Elijah, 6, at the Ward emergency welfare centre. Photo: RNZ / Kate Newton
On Ward beach, the coastal rock shelf was lifted by the force of the quake. Photo: RNZ / Kate Newton
The supermarket in Seddon suffered severe damage including collapsed ceiling panels. Photo: RNZ / Kate Newton
Seddon locals Richard Ronaki and Maki Kumasaka and their children Lyuta, 5, and Morena, 18 months. Photo: RNZ / Kate Newton
Someone made their feelings clear at a rockfall on Marlborough road. Photo: RNZ / Kate Newton
A closed section of State Highway 1 between Seddon and Kēkerengū. Photo: RNZ / Kate Newton
NZ Defence Force evacuation. Photo: RNZ / Rebekah Parsons-King
NZ Defence Force evacuation. Photo: RNZ / Rebekah Parsons-King
People are being evacuated by helicopter by the NZ Defence Force. Photo: RNZ / Rebekah Parsons-King
Chinese tourists evacuated. Photo: RNZ / Rebekah Parsons-King
Parents and children are evacuated from Kaikoura by the New Zealand Defence Force. Photo: NZDF
Families with young, old or vulnerable people are taking priority in evacuations. Photo: NZDF
New Zealand Defence personnel help evacuees settle in for their journey away from quake-stricken Kaikoura. Photo: NZDF
Four NZDF NH90 helicopters and commercial helicopters were helping evacuate tourists from the town. Photo: Supplied / NZDF
New World Kaikoura. Photo: RNZ / Rebekah Parsons-King
Plane lands on state highway 1. Photo: RNZ / Rebekah Parsons-King
Plane lands on state highway 1. Photo: RNZ / Rebekah Parsons-King
An image of Clarence River shows dust caused by an aftershock on November 14. Photo: AFP
Bricks have tumbled off this building in Culverden, one of the towns closest to the epicentre of Sunday nights quake. Photo: RNZ / Conan Young
Lines damaged on back road close to Waiau. Photo: RNZ / Conan Young
Lines damaged on back road close to Waiau. Photo: RNZ / Conan Young
Rockfalls along a closed portion of State Highway 1 just south of Seddon. Photo: RNZ / Kate Newton
Cracks in a closed section of State Highway 1 just south of Seddon. Photo: RNZ / Kate Newton
New Zealand Prime Minister John Key (R) inspects earthquake damage from a helicopter near Kaikoura. Photo: AFP
Former All Black captain Richie McCaw who has been flying personnel after the earthquake with Prime Minister John Key. Photo: RNZ
Elms Homestead. Photo: RNZ / Rebekah Parsons-King
Elms Homestead. Photo: RNZ / Rebekah Parsons-King
As the sun sets on day one of the quake, the town of Kaikoura will grow darker with many properties and businesses without power. Photo: RNZ / Rebekah Parsons-King
A Southland man flew to the area to check on friends and family, landing on State Highway 1. Photo: RNZ / Rebekah Parsons-King
Kaikoura township. Photo: RNZ / Rebekah Parsons-King
After feeding 700 people the clean up begins at Takahanga marae, local business owner Dexarelli helps out. Photo: RNZ / Rebekah Parsons-King
300 kg of crayfish waiting in the fridge at Takahanga marae for the hundreds of locals and stranded tourists tomorrow. Photo: RNZ / Rebekah Parsons-King
Damage outside the Kaikoura fire station. Photo: RNZ / Rebekah Parsons-King
Tourists attempt to make contact with their family after the quake. Photo: RNZ / Rebekah Parsons-King
A family reunites after the shakes in Kaikoura. Photo: RNZ / Rebekah Parsons-King
State Highway One near Oaro on the South Island's east coast. Photo: AFP
A crashed vehicle on SH1 in the wake of the devastating quake. Photo: AFP
A train is trapped by landslides on the Kaikoura coast line. Photo: AFP
Two significant fissures intersect a roadway near Rotherham. Photo: NZDF
Damage in the Mount Lyford area. Photo: RNZ / Rebekah Parsons-King
Railway cuts through State Highway 1 on the coastal road to Kaikoura. Photo: RNZ / Rebekah Parsons-King
Photo: RNZ / Rebekah Parsons-King
Damage to the road between Kaikoura and Mt Lyford. Photo: RNZ / Rebekah Parsons-King
A digger begins work on the road between Kaikoura and Mt Lyford. Photo: RNZ / Rebekah Parsons-King
A digger begins work on the road between Kaikoura and Mt Lyford. Photo: RNZ / Rebekah Parsons-King
Damage to the road between Kaikoura and Mt Lyford. Photo: RNZ / Rebekah Parsons-King
Lights seen above Wellington during yesterday's earthquake. Photo: Instagram: sana_aljoj
Road damage in the Waiau Valley/Mt Lyford area. Photo: RNZ / Rebekah Parsons-King
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Aerial surveys by Royal New Zealand Air Force aircraft showed massive rockfalls in several areas in the upper South Island. Photo: The New Zealand Defence Force
Two buildings on Picton's High Street damaged in Earthquake. Photo: RNZ / Tracy Neal
Acting Defence Minister Gerry Brownlee, Prime Minister John Key and entourage take off on blustery Wellington day heading to Kaikoura. Photo: RNZ / Mei Heron
Earthquake damage and slips around Kaikoura after the Hanmer Springs earthquake on November 14. Photo: Garden City Helicopters
Railway damage 20km south of Cheviot, as seen from the air. Photo: RNZ / Rebekah Parsons-King
Road damage 10km south of Clarence. Photo: RNZ / Rebekah Parsons-King
Earthquake damage and slips around Kaikoura after the Hanmer Springs earthquake on November 14. Photo: Garden City Helicopters
Earthquake damage and slips around Kaikoura after the Hanmer Springs earthquake on November 14. This is an inland slip. Photo: Garden City Helicopters
A house at Bluff Station between Blenheim & Kaikoura, which is right on the Kekerengu fault line, was demolished by the shakes. Photo: RNZ / Alex Perrottet
A house at Bluff Station between Blenheim & Kaikoura, which is right on the Kekerengu fault line, was demolished by the shakes. Photo: RNZ / Alex Perrottet
Damage at Wellington Port after the 7.5 quake hit near Hamner Springs. Photo: RNZ / Phil Pennington
Pictures of damage to home of Cheviot GP Anthea Prentice, at Claverley, near Cheviot. Photo: Supplied
Rail and bridge damage 20km south of Clarence. Photo: RNZ / Rebekah Parsons-King
Damage 20km south of Clarence, seen from the air. Photo: RNZ / Rebekah Parsons-King
Pictures of damage to the section of Cheviot GP Anthea Prentice, at Claverley, near Cheviot. Photo: Supplied
Road damage near Kaikoura. Photo: Twitter / @lou_gordongreen
Ohau Point on State Highway 1 has been completely blocked after this morning's shakes. Photo: Supplied / NZTA
A fresh landslide on the north east coast of South Island. Photo: RNZ / Alex Perrottet
Damage at Wellington Port after the 7.5 quake hit near Hamner Springs. Photo: RNZ / Phil Pennington
Broken windows in the Farmers Institute building on Featherston St, Wellington, after the 7.5 magnitude earthquake centred near Hanmer Springs. Photo: RNZ / Phil Pennington
MP Stuart Smith in Kaikoura. Photo: supplied
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
Earthquake damage around the Conway River area. Photo: Andrew Macfarlane
The Massey University campus in Wellington was closed. Photo: RNZ / John Gerritsen
Four Square Culverden owner Andrew Whittleston is thankful he's got a generator to keep his frozen goods on ice with power yet to be restored to the town. Photo: RNZ / Conan Young
Lines company working to restore power in North Canterbury Photo: RNZ / Conan Young
Damage on the state highway just before Hanmer Springs Photo: RNZ / Conan Young
Hundreds of people moved to higher ground on Mount Victoria, Wellington. Photo: RNZ / Rebekah Parsons-King
Broken glass in Wakefield Street in Wellington. Photo: RNZ / Rebekah Parsons-King
Broken glass on Cable St from an apartment building Photo: RNZ / Rebekah Parsons-King
Cars in the Wellington suburb of Mt Victoria after the earthquake. Photo: RNZ / Rebekah Parsons-King
Displaced Wellington residents Kenny Yeh, Daniel Sik and Alex Laing. Photo: RNZ / Rebekah Parsons-King
Evacuees at Amberley Pavillion, in North Canterbury, where a community welfare centre was set up in after the midnight earthquake. Photo: Conan Young /RNZ
Tea is served for evacuees at the Amberley Pavillion afte a 7.5 magnitude quake hit near Hanmer Springs. Photo: RNZ / Conan Young
The road towards Seddon has been closed. Photo: RNZ / Tracy Neal
The quake threw groceries off shelves and broke wine bottles at the Culverden 4 Square store. Photo: RNZ / Conan Young
The quake damage could be clearly seen on Leader Rd in Kaikoura. Photo: Twitter / @Nicola_RaynerNZ
The quake threw groceries off shelves and broke wine bottles at the Culverden. Photo:
RNZ / Conan Young
Richard Bicknell tweeted this picture of his kitchen after the severe earthquake. Photo: Twitter / Richard Bicknell
Earthquake damage in central Wellington. Photo: RNZ / Susie Ferguson
Pane of glass smashed from a window of a inner city building on The Terrace, Wellington. Photo: RNZ / Rebekah Parsons-King
An emergency sign at Massey University's Wellington campus. Photo: RNZ / John Gerritsen
Victoria Greenwood-Loose and Lexie Loose at the Tua Marina Memorial Hall in Marlborough, which was set up as a Civil Defence welfare centre. Photo: RNZ / Tracy Neal
Damage to road on The Terrace around a construction site. Photo: RNZ / Rebekah Parsons-King
Damage to road on The Terrace around a construction site. Photo: RNZ / Rebekah Parsons-King
A fresh landslide on the north east coast of South Island. Photo: RNZ / Alex Perrottet
The Good Vibes store on Manners St in Wellington. Photo: RNZ / John Gerritsen
A collapsed pile of logs at a Wellington wharf. Photo: AFP
Broken glass on a building in Manners St in Wellington. Photo: RNZ / Alexa Cook
Damage in a central Wellington store. Photo: RNZ / Alexa Cook
Tsunami activity was detected in Kaikoura and Wellington, with initial tsunami warnings prompting sirens from Northland to Christchurch, and waves detected in Wellington and the South Island.
A tsunami at least 2m high was recorded near Kaikoura, Civil Defence tweeted.
The Ministry of Civil Defence and Emergency Management has now cancelled the tsunami warning that was in place from Wellington to Banks Peninsula.
But it said coasts may still experience unusual, strong currents and sea level fluctuations lasting for several more hours.
KiwiRail said all trains on the North Island Main Trunk line, south of Palmerston North, and in the South Island had been cancelled until further notice.
Ferry sailings were also cancelled until a full assessment could be made of the terminals in Wellington and Picton.
The Ministry of Education advised schools and early childhood centres from North Canterbury through to Wellington would remain closed today.
It also said all NCEA Scholarship exams would be suspended.
Crack on state highway just before Hanmer Springs
Photo: RNZ / Conan Young
Canterbury
Houses were reported to be damaged in Kaikoura, with chimneys down in Culverden.
Police earlier said they were trying to get access to the Mt Lyford property where one person was thought to have died.
Three evacuation centres were open in Christchurch. At 5am there were 230 people at Linwood College, 50 at Mairehau School and 25 at Akaroa School Hall.
Hotel guests in central Christchurch were evacuated. More than 100 people stood on the footpath opposite the Christchurch Casino, while at least 100 hotel guests were outside the Novotel, opposite the Christ Church Cathedral.
Alan Vincent was on the water near Lyttelton near Christchurch when the quake struck. He said it felt like "giants shaking the living daylights out of the boat".
Cheviot firefighter Chris Hill said the roads were "a bit cut up".
A temporary boil water notice has been issued in Hurunui. A welfare centre was set up at the Amberley Pavilion.
Christchurch police have set up roadblocks to stop people going to coastal areas while a tsunami warning was in place.
Robin, from Christchurch, said the earthquake was a "wake-up call".
New Brighton resident Dean Kozanic evacuated his home as a precaution because of the tsunami warning. He said many residents in the suburb had been doing the same.
Power was cut in North Canterbury, from Kaikoura to Cheviot. The Hurunui District Council said Rotherham and Waiau were isolated by slips and damage to the bridge.
A fresh landslide on the north east coast of South Island
Photo: RNZ / Alex Perrottet
Northern South Island - train trapped
Marlborough Civil Defence controller Richard McNamara said a train had been trapped north of Kaikoura this morning.
"Our helicopter will drop in and check on the driver, we've been talking to train control South Island," Mr McNamara said early this morning.
"There'll be other people on the road that will be stuck and obviously the heavy traffic between Picton [at] the interisland ferry and Christchurch will also be held up."
He said bridges north of Blenheim had been damaged, but there was a diversion in place.
Fiona Redfern, of Muzzle Station on the Clarence River, warned neighbours on Facebook that the Dart Stream tributary had become dammed due to a slip and a flash flood could come at any time.
Several people spent hours stuck on the Interislander Ferry, which was unable to dock in Picton due to a power cut. Other ferry movements were suspended for the day.
Marlborough Civil Defence said buildings in Picton's main street were reported to be badly damaged, and the earthquake had caused liquefaction on the Picton foreshore.
Twenty people were receiving welfare help in the Ward Town Hall in Marlborough.
The area from Seddon to Ward had been checked by helicopters and some damage to electrical transmission poles had been found which could take days to repair.
There was a diversion in place on SH1 between Picton and Blenheim, which was open for some vehicles but heavier vehicles could not get through and were reported to be banked up for several kilometres along the highway.
Picton residents were asked to conserve water as one of the town's reservoirs was leaking.
An evacuation centre was being opened at the Waikawa Marae.
The Nelson Marlborough District Health Board said by early this morning five people had been admitted to Wairau Hospital with various injuries, some described as moderate.
Spark said its phone networks in Clarence, Kaikoura, Weld Cone, Waiau and Eltham in the South Island have been affected. People should text rather than call if possible, it said.
Power went out in many areas including Picton, Blenheim and Havelock.
Lansdowne Park in Blenheim was also closed due to liquefaction.
Damage at Wellington Port after the 7.5 quake hit near Hanmer Springs
Photo: RNZ / Phil Pennington
Wellington
Wellington City Council warned people not to go to work in the central city and Lower Hutt until the evening.
Several multi-story buildings received damage - both internally and structurally - and glass fell into streets.
Power was out in some areas, and Civil Defence controller Bruce Pepperell said early indications were that a number of major buildings showed signs of structural stress and the strong quake would likely have caused a mess inside.
Mr Pepperell said the capital's suburban rail network would not be operating until further notice, while rail tracks, bridges and tunnels were checked. Buses were unlikely to replace the trains.
He said 25 buildings in the CBD had so far been identified as having suffered potential structural damage.
"Certainly there's indications of some structural stress down in some of the buildings down in the CentrePort.
"There's a little bit of liquefaction down there, well, a lot of the CBD's on reclaimed land."
The damage had been referred to building owners for detailed examination by engineers, Mr Pepperell said.
Some city streets were showered with broken glass during the quake and it was feared strong winds tonight could dislodge more glass.
Land movement of up to 1m has been reported on reclaimed land on the waterfront with large cracks opening up in concreted areas.
Wellington Harbour Master Mike Pryce said he and port operator CentrePort were still assessing the earthquake damage to the waterfront including liquefaction.
CentrePort said it would issue an update on the situation shortly.
Victoria and Massey university campuses in the capital were closed this morning, with Massey saying exams would be postponed until further notice.
People who left their homes in the city centre were told they could find temporary refuge at the BizDojo Centre on 115 Tory Street, or Houghton Valley School further out of the city.
Residents in coastal areas were urged to stay inland or on high ground. Affected spots include seaside areas of Wellington's south coast, Seatoun and Eastbourne.
Broken glass in Wakefield Street in Wellington
Photo: RNZ / Rebekah Parsons-King
Otago
The state of emergency in Dunedin has been lifted after Civil Defence evacuated about 50 households in seaside communities.
Civil Defence in Otago said the land-based threat to the eastern coasts had passed and people were being allowed to go home.
The controller for Clutha district, Charles Hakkaart, said the main evacuations were in low-lying houses in Pounawea, Taieri Mouth and Toko Mouth.
The quake struck near Hanmer Springs
Photo: Supplied
Chatham Islands
About 40 people were evacuated from their homes on the Chatham Islands, mainly in the settlement of Kaingaroa, and more made their own way to higher ground.
Chatham Islands mayor Alfred Priest said the island was the path for tsunamis from both New Zealand and South America, and locals were good at responding to the threats.