A man driving south in northbound lanes of Interstate 5 in Carlsbad on Monday collided with another vehicle, causing serious injuries to himself and another driver, California Highway Patrol officials said.
The crash was reported around 8:15 p.m. on the freeway near Carmel Valley Road, CHP Officer Stephany Perez said.
The incident began when the wrong-way driver, a 38-year-old man in a Toyota Prius, crashed head-on into a Toyota RAV4 driven by a 37-year-old man, Perez said.
The two men, who are both from Carlsbad, were taken to a hospital, Perez said.
Investigators said they are looking into whether drugs or alcohol played a factor in the crash.
No other information was immediately available.
Officers asked anyone with information about the crash were asked to call the CHP office at (858) 293-6000.