The man was found dead, but it was not clear if the fatality was due to the crash or the medical seizure, officers said. The victims’ names were not immediately released.
The crash was at 5:41 p.m. Saturday. The driver of a 1997 Ford van lost control of his vehicle on southbound Interstate 15 approaching State Route 76, Oceanside CHP officer Jim Bettencourt said.
“According to witnesses, the driver suddenly started to veer to the right onto the right shoulder of the freeway’ and struck a tree,” Bettencourt said. “It is unknown why the driver veered off the freeway, but it appears the driver may have had a medical emergency.”
A passenger in the vehicle, a Carlsbad woman, 66, was not wearing a seat belt.
“She suffered major, life-threatening injuries due to the crash and was transported to Palomar Hospital,” Bettencourt said.
Bettencourt said it did not appear that alcohol or drugs were involved in the collision.
The incident remains under investigation.