At least one person is dead and 10 others were injured when a van drove into a group of worshippers outside a London mosque Sunday night in what police are investigating as a potential terrorist incident.

London’s Metropolitan Police said the man was pronounced dead at the scene. Eight others were taken to three area hospitals and two were treated at the scene.

The driver of the man, aged 48, was detained by members of the public at the scene and then arrested by police in connection with the incident, authorities said. He was taken to the hospital and will be subject to a mental health evaluation.

Counter-terrorism police were leading the investigation.

The Muslim Council said in a tweet that worshippers were struck by the van leaving prayers near Finsbury Park mosque. It said its prayers are with the victims.