The family of a man arrested after a terror attack near a north London mosque say they are "shocked" and "their hearts go out to the injured".
Ten people were injured, two of them seriously, and one died at the scene, when a van ploughed into worshippers close to the Muslim Welfare House in Finsbury on Monday.
A man held by police over the attack has been identified as Darren Osborne, a 47-year-old father of four from Cardiff, British media report.
In a statement on behalf of the family, Osborne's nephew Ellis Osborne, 26, said: "We are massively shocked; it's unbelievable, it still hasn't really sunk in."
Witnesses have described hearing the van driver, who was detained by members of the public at the scene, saying he had wanted to kill Muslims.
The van hit people who had been attending evening prayers at the Muslim Welfare House and the nearby Finsbury Park Mosque in north London, one of the biggest in Britain.
The pedestrians had been helping a man who had collapsed. He later died but it was not clear if it was because of the attack.
Mr Osborne was arrested on suspicion of attempted murder and alleged terror offences.
Police said the arrested man would be the "subject of a mental health assessment in due course".
Security Minister Ben Wallace said the suspect was not known to security services, and was believed to have acted alone.
Mr Osborne is understood to have grown up in Weston-super-Mare, Somerset, and have four children, the BBC reports. Police are carrying out searches at an address in the Cardiff area.
The attack was the fourth since March in Britain, and the third to involve a vehicle deliberately driven at pedestrians in London.
Prime Minister Theresa May said the attack was "every bit as sickening" as the others.
"It was an attack that once again targeted the ordinary and the innocent going about their daily lives - this time British Muslims as they left a mosque having broken their fast and prayed together at this sacred time of year," she said.
Mrs May was outside Downing Street after chairing a meeting of the government's emergency Cobra committee.
She later visited Finsbury Park Mosque where she held talks with faith leaders.
Police have said hate crimes rose after the London Bridge attack this month, when three attackers drover a van into pedestrians and then stabbed people, killing eight.
They said more officers would be deployed to provide reassurance to mosques.
Met Police Commissioner Cressida Dick said the incident was "quite clearly an attack on Muslims", and there would be more police, including armed officers, in the area, "particularly around religious establishments".
Mayor of London Sadiq Khan said: "While this appears to be an attack on a particular community, like the terrible attacks in Manchester, Westminster and London Bridge it is also an assault on all our shared values of tolerance, freedom and respect."
The imam of Muslim Welfare House - which is also a community centre - said a passing police van was flagged down after the attack.
Mohammed Mahmoud told reporters: "We told them the situation - there's a man, he's restrained, he mowed down a group of people with his van and there is a mob attempting to hurt him and if you don't take him then, God forbid, he might be seriously hurt.
"We pushed people away from him until he was safely taken by police."
- Reuters / BBC