In one of the worst crashes in California for decades, 13 people were killed and more than 30 others were injured when a tour bus hit a big rig near Palm Springs early Sunday morning, according to the California Highway Patrol. The driver of the bus was one of the fatalities in the wreck.

The cause of the crash is under investigation.

"We know that stretch of freeway has a fair amount of truck traffic," said Rosalie Murphy, reporter with the Desert Sun who has been covering the crash.

Federal safety officials are set to give a press conference this afternoon in Indio for more details about the fatal crash on the I-10 freeway.

Officials say they are still looking into what might have happened Sunday morning.

"They'll immediately begin a mechanical fitness inspection," said Collin Mooney, executive director of the Commercial Vehicle Safety Alliance, a nonprofit made up of local, state, and federal safety officials and industry representatives.

Click the blue audio player to hear the full interview.