SAN FRANCISCO (Reuters) - Two people died and at least nine more were injured when a Greyhound bus flipped over and came to rest straddling the median of a wet Northern California freeway, authorities said on Tuesday.

Two adult women were killed and an adult male has serious injuries following the predawn crash on U.S. Highway 101 south of San Jose, said California Highway Patrol officer Chris Miceli. Others including the driver had minor injuries, he said.

The bus struck a series of weighted barrels and then a concrete median separating the freeway from a one-lane flyover ramp to California Highway 85, Miceli said, causing the bus to turn over on its right side.

Images of the crash scene showed a crowd of emergency vehicles surrounding the bus, which had numerous broken windows and a crumpled front end.

Investigators and others dispatched to the crash scene expected hours of work before the bus can be removed and normal traffic access restored, he said.

Representatives for Greyhound could not be immediately reached for comment, but spokeswoman Lanesha Gipson told the San Francisco Chronicle newspaper that the bus company was fully cooperating with authorities.

A passenger on the bus told the Chronicle newspaper that the driver was asleep.

“He pulled over 5 miles ago to catch himself, but he didn’t have any energy,” the unidentified passenger told the newspaper.

The bus was carrying 20 people and had departed from Los Angeles Monday night with final stops in the San Francisco Bay Area, the Chronicle reported.