LOS ANGELES (Reuters) - Authorities searched for a gunman who opened fire from a speeding car on Monday at an ambulance, a police car and at least two other vehicles along a San Diego freeway, the California Highway Patrol said.

One man was struck in the leg by gunfire in the late-morning shootings, which prompted the Highway Patrol to close northbound lanes on a stretch of Interstate 805, but his wounds were not believed to be life-threatening, police said.

"The ambulance took some rounds," Highway Patrol spokesman Larry Landeros said, "but nobody was hit."

The suspect was seen firing shots out of a moving Chevy Malibu sedan with California license plates, and there were reports of such shootings at four different locations, Landeros said.

In addition to the ambulance, a Highway Patrol car also was targeted, police said.

(Reporting by Mary Slosson; Editing by Steve Gorman and Greg McCune)