Abdulraman Aidroos, who witnessed the incident, said "a white British man" shouted, "I am going to kill Muslims" before driving his vehicle into pedestrians.
London Mayor Sadiq Khan said following that attack that there had been a 40-percent increase in racist incidents in the city and a fivefold increase in the number of anti-Muslim incidents.
A helicopter could be heard circling over Finsbury Park as police erected a large cordon in the area. That number was later revised to one person killed and ten injured.
Someone in the crowd yelled to others not to harm the man while he was taken into custody.
"There was this white van stopped outside Finsbury Park mosque that seemed to have hit people who were coming out after prayers had finished".
She said: "I will chair an emergency meeting later this morning".
According to multiple reports and social media posts, the van ran over people leaving the Finsbury Park Mosque.
Police have not offered any details about the cause of the crash.
Police said the driver was detained by the crowd until police arrived.More news: Senate approves new Russia sanctions
Police have confirmed that one person was pronounced dead at the scene after officers were called to Seven Sisters Road just after 12.20 BST.
Norris said he saw the driver of the van running toward a gate before being caught by a group of men. CNN is reporting that the incident occurred near a mosque as people were leaving a service. Two others were treated at the scene for minor injuries.
The investigation is being undertaken by the police's counter-terrorism command.
Britain set its terror at "severe", meaning an attack is highly likely, after a pair of incidents recently.
He told BuzzFeed: "I think at least eight or 10 people got injured".
Police arrested the van's driver, but were trying to determine whether the collision was accidental or deliberate. The Finsbury Park Mosque was once considered as the hub for the Radicalization in the United Kingdom.
Vanzella said the north London community is very diverse, with churches of various faiths within blocks of one another.
Ms May says her thoughts are with all those injured in the "terrible incident". Eight injured were sent to three separate hospitals and two others were treated at the scene.
Prime Minister Theresa May's office says she has been told about the crash in north London in which a vehicle struck several pedestrians.
"I have also spoken with community organisations in the area, local MP Jeremy Corbyn and leader of the council Richard Watts". "Our prayers are with the victims", it said. Ambulance crews said ten people had been transferred to hospital. "Our prayers are with the victims".