At least five people were injured Saturday evening in a collision that the California Highway Patrol said involved five motorcycles and two passenger vehicles on the 210 Freeway in Irwindale.
Firefighter-paramedics responded shortly after 7 p.m. to the westbound side of the freeway, just west of Irwindale Avenue, a supervisor with the Los Angeles County Fire Department said.
Five or six people were hurt in the crash, according to the Fire Department. Their conditions were not immediately known.
Several motorcyclists, who were not involved in the pileup, stopped to render assistance, according to a CHP incident log.
Four flatbed tow trucks were requested to remove the damaged motorcycles and other vehicles involved in the collision, including a BMW sedan that had been carrying four occupants, the log stated.
The CHP issued a SigAlert for the westbound 210, and the No. 1, No. 2 and carpool lanes were closed for more than an hour, the agency said on Twitter.
According to tweets from the Irwindale Police Department, traffic was heavy in both directions at the crash site. Motorists were advised to avoid the area while a cleanup operation was underway.
The SigAlert was later canceled and all lanes were reopened as of 8:40 p.m., police and the CHP said.
The cause of the incident was unknown.