One person was killed when two vehicles collided head on Monday afternoon on state Route 67 near Ramona, authorities said.
A third vehicle was also involved in the crash, which happened about 4:15 p.m. on the two-lane highway near Mussey Grade Road, according to the California Highway Patrol and Cal Fire San Diego.
Firefighters immediately began performing CPR on a gravely injured person when they arrived at the scene, Cal Fire spokesperson Capt. Frank LoCoco said. Despite those efforts, that person died.
Information about the victim was not immediately available.
A second person sustained mild injuries and was treated by paramedics at the scene and released, LoCoco said. A third person was uninjured.
According to a Highway Patrol incident log, the crash involved at least two sedans and a third vehicle. One of the cars ended up in a ditch off the highway.
Authorities shut down the southbound lane of the highway and issued a traffic alert for the area. LoCoco said the highway was likely to remain closed for several hours.