A car crashed Thursday into the gates of Downing Street in central London, home to the British prime minister’s home and office, triggering a rapid security response at one of London’s most fortified locations.

The Metropolitan Police said a man was arrested on Thursday afternoon at the scene on suspicion of criminal damage and dangerous driving. There were no reports of injuries.

Prime Minister Rishi Sunak was in his office then.

Video footage posted on social media showed a silver estate car heading straight for the gates at low speed across Whitehall, the main street in London’s government district.

Footage taken soon after showed a car with its tailgate open against the high metal gates. Several officers inspected the vehicle thoroughly, removing items from the trunk and inside the car and placing them in evidence bags.

It was not immediately clear if the crash was intentional. Police said they are working to determine the circumstances.

“I heard a bang and looked up to see loads of police with guns shouting at the man,” said witness Simon Parry, 44. “A lot of police vehicles came very quickly and were very quick to evacuate the area.”

The BBC showed a photo of police officers leading a man away with handcuffs behind his back.

Police cordoned off a wide area after the crash but began lifting the barriers within half an hour, allowing people back into Whitehall, which normally throngs with officials and tourists keen to see the nearby Houses of Parliament and other historic buildings.

Downing Street is a narrow street with a row of Georgian houses including the Prime Minister’s official residence at No. 10.

Public access to the street is limited and the heavy steel gates are guarded at all times by armed police. Concrete bollards and metal crowd barriers also help keep threats at bay.

The gates were erected in 1989 in response to threats from Irish Republican Army militants.

In 1991, the IRA fired three grenade launchers into the street, one of which exploded in the backyard of No 10 while Prime Minister John Major was chairing a Cabinet meeting inside. Three police officers and an official received minor injuries.

The area was targeted in 2017 when an Islamic State-inspired extremist killed four people with a vehicle on Westminster Bridge before stabbing a police officer to death outside Parliament.