At least two people were injured in a crash involving five vehicles, including a semi-truck, on an exit ramp from southbound state Route 163 in Mission Valley, officials said.
The crash happened at about noon on the off-ramp from SR-163 to Friars Road.
San Diego Fire-Rescue crews arrived to the scene and transported two people to Scripps Mercy Hospital in serious condition.
The agency's Hazardous Materials team also responded to the crash due to a spill from the semi-truck. About 50 gallons of fuel leaked onto the roadway.
The offramp to Friars Road was shut down until about 4:30 p.m. as crews cleaned up the mess.