A one-in-a-million artillery fuze malfunction caused shrapnel to rain down on California Highway Patrol vehicles during a live-fire demonstration for Vice President JD Vance and Defense Secretary Pete Hegseth at Camp Pendleton in October. The Marine Corps investigation found that an electronic time fuze designed to explode after a calculated delay instead detonated prematurely over Interstate 5 at 1,529 feet altitude.

Six M777 howitzers were positioned on Red Beach for the 250th anniversary celebration, with two guns placed just 14 feet apart - closer than typical training configurations. The report cited possible causes including near-simultaneous firing of howitzers and potential electromagnetic interference. Only one previous incident with this M767A1 fuze type occurred in 2017 when a shell hit a bird midair.

The politically charged event sparked controversy when Governor Gavin Newsom ordered a 17-mile freeway closure hours before the demonstration, drawing White House criticism. The Marines determined personnel were not at fault, noting the fuzes were manufactured by BT Fuze Products in 2004 and certified to a one-in-a-million defect standard.