A rare incident during a live fire demonstration at Camp Pendleton left highway traffic stunned as shrapnel unexpectedly showered Interstate 5 last October. The U.S. Marine Corps’ investigation into the event, which occurred during the 250th anniversary celebration of the Marine Corps, revealed that the misfire struck two California Highway Patrol vehicles. Thankfully, no injuries were reported.
Investigation Findings
The mishap involved an artillery shell detonating prematurely over the highway that connects Los Angeles and San Diego, an area bustling with civilian activity. The Marine Corps’ investigation, documented in a 666-page report, found no negligence or misconduct by the Corps members. The report noted that the premature detonation of the M795 high explosive round, occurring at an altitude of about 1,480 feet, was an unpredictable event.
“It is manufactured to a tolerance of one defect in a million,” the report stated, highlighting the rarity of such an incident. A total of 60 rounds were intended to be fired during the demonstration, but the early detonation led to the cancellation of the event following the first volley.
Controversy and Response
The demonstration, attended by Vice President JD Vance and Defense Secretary Pete Hegseth, drew criticism from Democratic Gov. Gavin Newsom, who had previously labeled the live fire exercise as dangerous. Newsom ordered the closure of I-5 during the event, a decision that faced backlash from the White House and Republican figures. The Marine Corps had assured that the exercise posed no threat to motorists.
Following the incident, 26 California U.S. House members and the state’s two senators addressed a letter to Hegseth, questioning the rationale behind the decision to conduct live artillery exercises over a major freeway and the safety measures in place.
Potential Causes
The Marine report speculated on various factors that might have contributed to the malfunction, including the proximity of the howitzer guns and the possible existence of anomalous electromagnetic energy in the area. Despite thorough investigations, the exact cause of the malfunction remains elusive.
“What 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 stated.
Incident Details
The artillery round was launched at 1:46 p.m. from M777 howitzers, located on a beach west of Interstate 5. The detonation sent shrapnel towards a CHP motorcycle and another unoccupied patrol vehicle. The vehicles were part of a protective service detail for Vice President Vance, according to the CHP report. The officer on the motorcycle reported hearing what resembled “pebbles” hitting his vehicle and discovered fragments nearby.
CHP sergeants conducted a safety inspection of the highway but found no additional metal pieces on the roadway. Traffic resumed on both sides of the highway within 30 minutes.
Public Reaction
Despite the incident, several individuals involved in the Marine investigation expressed that they would not alter the event’s execution. They noted that a rehearsal conducted the previous day had proceeded without issues, and safety measures were diligently observed.
The Camp Pendleton celebration featured a display of military might, including aircraft, ships, and amphibious vehicles, aimed at marking the historic anniversary of the Marine Corps. “It will be a good show regardless of who shows up,” Gen. Eric Smith, commandant of the Marine Corps, commented in an email prior to the event.
