A new kind of cyber attack is emerging in New Zealand - cyber ransoming, where hackers seize files or intellectual property, and demand money before they are returned.
The minister in charge of New Zealand's spy agencies, Chris Finlayson, said he has recently become aware of one of the first New Zealand cases of cyber ransom.
He said he was told about the incident on a recent visit to Christchurch, while talking to members of the city's Muslim community.
He made the comments while attending the inaugural National Security Conference today, which was hosted by Massey University in Auckland.
Mr Finlayson was talking about the increasing threat of cyber attacks on government agencies, as well as New Zealand companies.
"The world has advanced in the last 25 years, the growth of the internet has mean that huge amounts of information is available, but also in this area, cyber security questions are increasingly important.
"And I go back to what just happened a little while ago with the Bank of Bangladesh - someone got into their system and $100 million was taken. We all know what happened to Sony, they suffered calamitous losses of about $US400 million."
Mr Finlayson said security could no longer be seen in the traditional context of a country's physical borders.
"Because physical borders are one thing but cyber borders are another, and these sorts of things are happening on a regular basis. We're all told as private citizens, cover your number when you go to the ATM and things like that.
"But these sorts of things are becoming more common and the effect on a New Zealand company of a cyber intrusion and what one gets these days - cyber ransoming - is actually a very serious matter."
Mr Finlayson said he was in Christchurch recently talking to members of that city's Muslim community, when someone stood up and said he had been a victim of cyber ransoming.
"What happens is they get into your system, they may take a whole lot of files and say - pay me $20,000 or you won't be getting them back."
He said he was not aware of any government departments having been targeted in that way, and the example in Christchurch was the first example he had heard of in the New Zealand context.
GCSB head Andrew Hampton said each month the agency became aware of 900 different malware signatures, or different types of attacks.
"We become aware of this because of information we get from our partners as well as what we're seeing in New Zealand; also within any one month up to seven of the agencies or organisations we support are suffering some sort of intrusion."
Mr Hampton said there were two new main types of attacks - credential harvesting, such as someone trying to steal your password, and what was known as "ransomware".
"When someone locks down your system and demands that you pay a fee in order to free it up."
Anyone targeted by a cyber attack was encouraged to contact their internet service provider and an enforcement agency such as the police.