A Manhattan Beach police patrol car and an SUV collided late Wednesday night at 9th Street and Sepulveda Boulevard.
The officer was rushed to the hospital. Officials said he was in stable condition and is expected to make a full recovery. The woman in the SUV was not seriously hurt.
The cruiser was traveling northbound on Sepulveda Boulevard, heading to a priority one emergency when it sideswiped the SUV, according to authorities. They did not say what the emergency was.
One witness at the scene said the cruiser was going so fast that it sounded like a pursuit.
"We had a lot of fast vehicles going down and we heard a huge boom," he said.
All lanes of Sepulveda Boulevard from Manhattan Beach Boulevard to 2nd Street were expected to be shut down until about 10 a.m.
The cause of the crash remains under investigation.