Nine people were hospitalised after a white driver, who witnesses said shouted: "I want to kill all Muslims", slammed into a crowd near a mosque in the Finsbury Park area of London.
One elderly man, who had collapsed moments before the van appeared, was pronounced dead at the scene, although police have not yet confirmed whether he died as a result of the attack.
Locals held onto the suspect until he was detained by police and later arrested on charges of "the commission, preparation or instigation of terrorism including murder and attempted murder."
The terror probe led investigators to the Welsh capital Cardiff, where they searched a property said by media to be the home of Darren Osborne.
Five residents speaking to the Press Association journalists identified images of the man being arrested as their neighbour, Osborne.
"I know him. I've lived here for five years, he was already living here when I moved in," said 50-year-old Saleem Naema.
"If I ever needed anything he would come. I just can't believe that he did that. I am a Muslim."
"I saw him on the news and I thought 'Oh my God' that is my neighbour.
"He has been so normal. He was in his kitchen yesterday afternoon singing with his kids," she told AFP.
Another neighbour said Osborne could often be seen in the street arguing with his wife.
A woman living next door to the property being searched told an AFP photographer her neighbour was Osborne, without linking him directly to the attack.
The BBC was among other media which identified the man arrested as Osborne, while London's Metropolitan Police said it would not name the suspect until he was charged.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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