A pickup truck plummeted 60 feet from a San Diego overpass on Saturday, crushing and killing four people who were attending a festival and injuring nine.



The truck was driven by Richard Anthony Sepolio, 25, a U.S. Navy member who police suspect was drunk. The four people killed ranged in age from 49 to 62 and have not been identified.



The crash shattered a motorcycle festival at Chicano Park, where hundreds had gathered on a clear, sunny day. The truck landed on a tent selling T-shirts just steps from the front of a stage where a rockabilly band was playing. Festival attendees sprinted to the wreckage, lifting the battered truck to try to free the injured.



"It looked like Superman had thrown a car right off a bridge," Dolores D'Angelo told San Diego's NBC 7. "Pieces of car parts were flying all over the place.



"When we got up, we turned around, everybody started running over there because we realized, there were people sitting there - there were people sitting right there."



The park was the ending point for La Raza Run, a motorcycle ride from Los Angeles to San Diego that had started about 8 a.m. Saturday. The San Diego Tribune reported that up to 2,000 bikers left downtown Los Angeles on Saturday morning headed for San Diego.



Motorcyclists and others arrived at the park around 12:30 p.m. By 3:30, a large crowd had gathered, looking at art, perusing a VIP raffle and listening to live music.



On the freeway above at about the same time, Sepolio was trying to get from a northbound lane onto Interstate 5, troopers said. He lost control of the tan truck, which ran through a guard rail and plunged into the park.



The scene was "instant chaos and panic," one attendee told the Tribune.



As first responders and attendees rushed to help the victims, Sepolio, apparently in shock, asked someone to call his commanding officer. He was taken to the hospital and ultimately charged with DUI causing death.



"It's horrible. Its horrific," Officer Jake Sanchez of the California Highway Patrol told reporters. "Innocent people were down here having a good time."



By nightfall Saturday, an impromptu memorial had sprung up at the scene of the wreckage, with more than a dozen candles forming a cross.