A vehicle struck pedestrians near a mosque in north London early Monday morning, killing one man and injuring 10 other people in what police are investigating as a terrorist incident.

Police said the 48-year-old man who was driving the car has been arrested and taken to a hospital as a precaution. He will be given a mental health evaluation.

The crash occurred at a time when the multiethnic neighborhood was crowded with Muslims leaving the Finsbury Park mosque after Ramadan prayers. Muslim leaders called it a hate crime and asked the public to stay calm.

Police said the driver was detained by the crowd until police arrived.

Prime Minister Theresa May condemned the attack, calling it a "sickening" attempt to destroy freedom of religion. She added that Britain would "stop at nothing" to defeat extremism.

May earlier said she would chair an emergency security Cabinet session Monday. Britain's terrorist alert has been set at "severe," meaning an attack is highly likely.

[NATL] Photos: UK Police Respond After Van Runs Over Crowd Near London Mosque

The crash occurred shortly after midnight, when police received reports of a collision between a van and pedestrians. Police said eight of the injured were hospitalized; the other two had minor injuries and were treated at the scene.

Eyewitnesses reported seeing police give emergency heart massage to at least one of the injured.

A leader of the Muslim Council of Britain called for extra security at mosques in light of the apparent attack. The group's general secretary, Harun Khan, described the incident as a hate crime against Muslims.

"During the night, ordinary British citizens were set upon while they were going about their lives, completing their night worship," he said. "It appears from eyewitness accounts that the perpetrator was motivated by Islamophobia."

London Mayor Sadiq Khan, the first Muslim to serve in that position, said extra police would be deployed. He called the incident a "horrific terrorist attack."

Video filmed in the immediate aftermath showed a Caucasian man being detained by police.

Someone in the crowd yelled to others not to harm the man while he was taken into custody. The video of the crash early Monday morning was accessed by the AP.

Someone in the crowd is heard shouting, "No one touch him! No one! No one!"

The chairman of the Finsbury Park Mosque says the van crash that hit worshippers was a "cowardly attack" and urged Muslims going to mosques to be vigilant.

Mohammed Kozbar said the Muslim community is "in shock." He complained that the "mainstream media" was unwilling to call the attack a terrorist incident for many hours.

London police closed the area to normal traffic. A helicopter circled above the area as a large cordon was established to keep motorists and pedestrians away.

Eyewitnesses told British media that the van seemed to have veered and hit people intentionally.

Mohammed Shafiq of the Ramadhan Foundation, a Muslim organization, said that based on eyewitness reports, it seems to be a "deliberate attack against innocent Muslims."

The Finsbury Park mosque was associated with extremist ideology for several years after the 9/11 attacks in the United States, but was shut down and reorganized. It has not been associated with radical views for more than a decade.

It is located a short walk away from Emirates Stadium, home of the Arsenal football club in north London.

The leader of the opposition Labour Party Jeremy Corbyn also spoke about the crash, writing on Twitter that he was "totally shocked."

"My thoughts are with those and the community affected by this awful incident," he wrote.

Other public figures also took to social media in response to the attack.

Thoughts & prayers with all those affected by the horrific terrorist attack on innocent people in #FinsburyPark. https://t.co/mbBCS9Gaad pic.twitter.com/Fvhl3DOAV4 — Sadiq Khan (@SadiqKhan) June 19, 2017

Earlier this month, a van veered into pedestrians on London Bridge, setting off vehicle and knife attacks that killed eight people and wounded many others on the bridge and in the nearby Borough Market area. Three Muslim extremists who carried out the attack were killed by police.

Manchester was also hit by a severe attack when a bomber killed more than 20 people at an Ariana Grande concert.