SAN LEANDRO -- A 16-year-old boy was hit in the head with a baseball bat and then shot in the shoulder Wednesday afternoon in unincorporated San Leandro, authorities said.

The boy is expected to survive, authorities said.

Alameda County Sheriff's Office spokesman Sgt. J.D. Nelson said the boy and another teen were walking on 163rd Avenue toward E. 14th when a man they did not know confronted them holding a baseball bat in an aggressive manner. One boy ran away and the 16-year-old was hit and then shot, Nelson said. The man then ran back to his car, a silver four-door sedan, and drove away.

No arrests have been made.

A description of the suspect and a motive were not released.

Anyone with information is asked to call the sheriff's office at 510-667-3636.

Follow Kristin J. Bender at Twitter.com/kjbender.