iStock/Thinkstock(LONDON) — Police in London are investigating what they call a “major incident” after a vehicle Sunday night reportedly collided with pedestrians gathered outside a mosque after prayers, leaving several people injured.

Eyewitnesses said there were a total of three “attackers,” one of whom was apprehended while two more fled the scene.

A British Muslim group said the people struck down by the vehicle were worshipers leaving a mosque. The incident happened in Finsbury Park in the north of London, in Seven Sisters Road, according to officials.

Prime Minister Theresa May called it a “terrible incident,” and said: “All my thoughts are with those who have been injured, their loved ones and the emergency services on the scene.”

The eyewitnesses interviewed by ABC News said people were gathered outside the mosque after prayers tending to an old man who was having a heart attack when the van drove into them. There were men, old men and women, no children. Anywhere from five to 11 people were mowed down, the witnesses said.

The Muslim Council of Britain tweeted out a statement saying, “We have been informed a van has run over worshippers as they left prayers at the Finsbury Park Mosque,” but later said the incident occurred outside Muslim Welfare House, which is near the mosque, “not outside Finsbury Park mosque itself.”

A man identified as Jermain Jackman told the BBC the sidewalks were “packed with people walking home” when the incident occurred.

“It was a van that mounted the pavement as men and women were leaving the mosque to go home to their families and friends and their loved ones,” Jackson said.

There were officers on the scene with emergency responders, treating a number of injured people, according to the Metropolitan Police.

London Ambulance tweeted: “We have sent a number of resources to an incident in Seven Sisters Road.”

One person was in custody and the investigation was ongoing, police said.

Britain set its terror at “severe,” meaning an attack is highly likely, after a pair of incidents recently.

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

There was also an attack at an Ariana Grande concert in Manchester, where a bomber set off an explosion that killed more than 20 people.

Witnesses posted on social media about armed police closing off the area and seeing people injured.

Armed police on the scene #FinsburyPark pic.twitter.com/LeRd6NAE2k

— Ali Habib (@Habibiline) June 19, 2017

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