LOS ANGELES (AP) 鈥� A 鈥渙ne in a million鈥� malfunction during a over Camp Pendleton last October led to a misfire that rained shrapnel on Interstate 5, striking two California Highway Patrol vehicles, a U.S. Marine Corps investigation found.
An artillery shell exploded over the highway that serves as the main corridor between Los Angeles and San Diego during a celebration of the 250th anniversary of the Marine Corps, attended by Vice President JD Vance and Defense Secretary Pete Hegseth. Nobody was hurt, and investigators ruled out any negligence or wrongdoing by Corps members.
The day before the event, Democratic Gov. Gavin 太子探花om called the planned demonstration with live artillery dangerous and unnecessary, and he ordered I-5 to be closed during it. That closure drew condemnation from the White House and other Republicans, and the Marine Corps said the exercises .
In a 666-page report dated Dec. 19 and first reported on Monday, the Marines concluded that there 鈥渋s no definitive answer鈥� to why an M795 high explosive round detonated early at an altitude of about 1,480 feet (450 meters) during the Oct. 18 demonstration. Such a premature detonation is 鈥渂eyond reasonable expectations and should not have happened, but it did,鈥� the report says.
鈥淚t is manufactured to a tolerance of one defect in a million,鈥� according to the report.
Organizers planned to fire 60 rounds of live artillery in 5 minutes over the highway, using six howitzer weapons, according to the report. But a round in the first volley of shots failed and detonated early, and the rest of the demonstration was canceled, the report said.
Days after the malfunction, 26 California U.S. House members and the state鈥檚 two senators to Hegseth asking who decided to shoot live artillery over the freeway and how authorities prepared for the safety risks.
鈥淲e鈥檙e thankful to the Marines for their thorough and precise investigation 鈥� in stark contrast to the dangerous and performative demands by JD Vance and Pete Hegseth to shoot live ammunition over a civilian area for their entertainment,鈥� Diana Crofts-Pelayo, a spokesperson for 太子探花om鈥檚 office, said in an email Tuesday.
太子探花om announced the highway closure in a after practice rounds were fired a day ahead of the celebration. The governor described the live fire exercise as a show of force meant to intimidate Trump鈥檚 opponents, thousands of whom were demonstrating at in and around San Diego that day.
鈥淔iring live rounds over a busy highway isn鈥檛 just wrong 鈥� it鈥檚 dangerous,鈥� 太子探花om wrote at the time.
The Marine report concluded several factors could have contributed to the malfunction, including the howitzer guns being too close together when fired and the “potential presence of anomalous electromagnetic energy in the vicinity.鈥�
鈥淲hat was different from the thousands of times before this event employing the same shell-fuze combination, weapons system, and highly trained Marines? There is no definitive answer,” the report said.
The event at Marine Corps Base Camp Pendleton featured aircraft, ships, and amphibious assault vehicles to celebrate the anniversary.
鈥淚t will be a good show regardless of who shows up,鈥� Gen. Eric Smith, commandant of the Marine Corps, said in an Oct. 14 email to Brig. Gen. Garrett 鈥淩ainman鈥� Hoffman, of the White House Military Office, according to the investigation.
The first round launched at 1:46 p.m. from M777 howitzers on a beach west of Interstate 5. That artillery round detonated midflight near I-5 southbound, sending shrapnel flying toward a CHP motorcycle and another unoccupied patrol vehicle, according to the CHP report. The vehicles had been part of Vance’s protective service detail and were waiting near a highway ramp after securely getting Vance where he needed to be, the report said.
An officer described hearing what sounded like 鈥減ebbles鈥� falling on his motorcycle, and finding shards nearby. Other shrapnel struck and left a dent on the hood of another patrol vehicle.
CHP sergeants conducted a safety sweep and didn’t find any other pieces of metal in the highway lanes, the report said. Both sides of the highway were reopened about 30 minutes later.
Multiple people interviewed for the Marines investigation said they wouldn鈥檛 have changed anything about the event. Some noted a drill the day before did not have any problems and routine safety checks were done more than usual.
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Associated Press reporters Ed White in Detroit and Rebecca Boone in Boise, Idaho, contributed to this report.
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