At least 20 people have been injured after a vehicle drove into a crowd on Santa Monica Boulevard in Los Angeles, according to the Los Angeles Fire Department (LAFD).
Up to five people have been critically injured and up to 10 are in a serious condition, the emergency services said.
The incident happened at 02:00 local time (09:00 GMT) in East Hollywood.
Pictures from the scene show a grey car on a pavement with debris strewn on the ground, and a large police presence.
The location of the incident given by the LAFD is near a music venue, CNN has reported.
It is not currently clear what caused the vehicle to drive into the crowd.
The people affected have all been transported to local hospitals or trauma centres, LAFD Captain Adam VanGerpen told reporters at the scene.
He said the majority of those in the crowd were were women waiting in line to go into a nightclub.
“It was a very chaotic scene,” Capt VanGerpen said, adding that “a lot of bystanders by the club came out to help people”.