A tour bus has crashed into the back of a tractor-trailer on a Southern California highway, killing at least 13 people and injuring 31, local media reports.
The crash occurred on a highway near Palm Springs, a city about 160km east of Los Angeles, an NBC affiliate reports.
The Riverside County Coroner's Office confirmed 13 people aboard the bus were killed, the station said.
Photographs from the scene showed the front of the tour bus wedged inside the back of the trailer, with emergency workers using metal ladders to reach the inside of the bus.
A tow truck was used to separate the vehicles, local media including the Desert Sun newspaper reported.
The injured were being treated at local hospitals, while all westbound lanes of the interstate were closed near the crash, according to the reports.
The bus had left the Red Earth Casino in Salton City, California, and was headed to Los Angeles when the crash was reported to the California Highway Patrol.
- Reuters, AAP