Los Angeles County fire officials say 50 people have been injured in a tour bus crash along a Southern California freeway.

Fire Department supervisor Bryan Webb says five were flown by helicopters to a trauma center, but most of the others are believed to have relatively minor injuries.

The bus went off the side of the highway Thursday morning and ended up on its side.

An employee of a travel agency called Da Zhen says the bus was heading to a casino.

The route is commonly used for "gamblers' specials" that take tourists to desert casinos and Las Vegas.