Authorities say the officer was investigating a solo-vehicle crash on the Perris Boulevard off-ramp at about 8 a.m. An ambulance and the Moreno Valley Fire Department had also responded.
During the investigation, an out-of-control Toyota sedan spun across lanes and slammed into the ambulance. A CHP officer and a civilian, who were both standing next to the ambulance, were struck. The driver of the Toyota and a civilian suffered major injuries, and the officer suffered moderate injuries, authorities said.
The crash is under investigation.