Update: 13 people were killed Sunday morning in a crash involving a tour bus and a semi-truck on the 10 Freeway north of Palm Springs, according to CHP. 

The incident prompted the closure of all westbound lanes on the freeway, according to the California Highway Patrol.

The crash happened at about 5:17 a.m. on the westbound side of the interstate, just west of Indian Canyon Drive, the CHP said.

The cause of the collision and the number of injuries were not immediately known, a spokesperson for the Highway Patrol's Indio office said.