An as-yet unidentified man was killed in a solo crash Saturday morning as he sped across the Bay Bridge in a stolen car.

According to California Highway Patrol spokesperson Officer Vu Williams, the driver of a 1998 Acura Integra was traveling at over 100 miles an hour on eastbound Interstate 80 just west of the First Street on-ramp at 6 a.m. Saturday.

That's when witnesses say the man, described only as "in his 30s," appeared to lose control of the car.

The driver crashed into the wall at the left side of the freeway, then slid into the gravel shoulder next to the on-ramp before slamming into one of the bridge's concrete support pillars, Williams says.

Good samaritans who'd witnessed the collision stopped and pulled the driver from the vehicle, which had started to catch on fire. He was pronounced dead at the scene, Williams says.

According to Williams, the Acura had been reported stolen in San Francisco previous to the crash. He says the cause of the collision remains under investigation.