THE driver and passenger in an ambulance were seriously injured after it was involved in a collision with a bus.
West Yorkshire Police said four people on the bus were also hurt, including the driver who was trapped.
The ambulance was said to have been responding to an emergency call with its blue lights flashing at about 10.35 last night.
It was involved in the collision at the junction of Hunslet Road and Black Bull Street in Leeds.
The ambulance fell on its side.
Police said there was no one in the rear of the vehicle.
A police spokesman said: "A bus collided with an ambulance responding to an emergency call with its blue lights activated.
"As a result of the collision, the ambulance turned on its side and the driver and passenger received injuries which appear to be serious but not life threatening."
The spokesman said the cause of the accident was being investigated.