On February 28, 1975, at 7:40 a.m., P.d.t., the first of a series of multiple-vehicle collisions occurred on State Route 91 near Corona, California. The collisions occurred in fog. Personnel of the California Highway Patrol had started to escort some vehicles through the fog in convoys when the collisions occurred. The vehicles in the convoys were not involved in the serious collisions.
The highway was closed for about 4 hours. There were no fatalities. Twenty-three persons were injured, 6 of whom were hospitalized. About 60 automobiles and 24 commercial-trucks were involved. Fire began when a truck struck an automobile.