A bomb has exploded inside a car outside the courthouse in Londonderry.
The explosion occurred in Bishop Street at about 20:15 GMT on Saturday, shortly after police received a warning.
Officers were on the scene when the blast occurred. No one is believed to have been injured.
Police had just started evacuating nearby buildings, including a hotel, when the explosion took place. A cordon remains in place at the scene.
Local politicians have told the BBC that the vehicle was hijacked in Derry some time before the explosion.
An eyewitness told the BBC: “The remains of the car could still be seen burning in the middle of the road.
“A cordon has been set up around the scene and police are evacuating more buildings on Bishop Street.”