VISTA, Calif. -- Authorities are searching for a hit-and-run driver blamed for seriously injuring a 15-year-old boy riding his skateboard in Vista.

The boy was struck by a dark sport utility vehicle or a pickup truck while walking eastbound across East Vista Way at Arcadia Avenue shortly before 9:30 p.m. Monday, said San Diego County sheriff's Deputy Dwain Washington.

He was carried on top of the hood of the suspect's vehicle before rolling off and landing on the asphalt roadway, Washington said, adding that the boy suffered major head trauma and possible internal bleeding.

Paramedics flew the boy to Palomar Medical Center.

The driver, who made no attempt to stop, was last seen headed southbound on East Vista Way, Washington said. It was unclear whether the driver was male or female.