A man called for help around 11 p.m. Monday and said he had been shot in the chest by someone inside a newer-model white sedan, like a Scion, while traveling along northbound Interstate 5 near SeaWorld Drive, according to CHP Officer Jake Sanchez.
"The victim and the suspect were actively engaged in a road rage altercation," he said.
The wounded driver pulled over immediately after being shot, and the suspect exited the freeway at Clairemont Drive, according to Sanchez.
The wounded man, whose name was not released, was taken to Scripps Memorial Hospital La Jolla, a San Diego Fire-Rescue Department dispatcher said.
The driver of the suspect vehicle was described as 20 to 30 years old, with short hair. A woman was in the front passenger seat.
The CHP asked anyone with information to call (619) 220-5492.