Shrapnel from artillery rounds fired by the US Marine Corps during a celebration in front of Vice President JD Vance and Secretary of War Pete Hegseth detonated prematurely and struck a patrol car, the California Highway Patrol said.
The artillery shells were fired over Interstate 5 near Camp Pendleton in San Diego County as part of a military demonstration for the 250th anniversary of the Marine Corps. anniversary.
The live-fire demonstration also coincided with the “No Kings” protests against President Donald Trump and his administration that were occurring throughout Southern California and across the country.
United States Vice President JD Vance speaks at the United States Marine Corps 250th Birthday Celebration at Marine Corps Base Camp Pendleton October 18, 2025 in Oceanside, California. The US Marines mark their 250th anniversary with a live amphibious assault demonstration titled “Sea to Coast: An Amphibious Force Review” and visits from Vice President JD Vance and Secretary of War Pete Hegseth.
Mario Tama/Getty Images
A 17-mile stretch of the busy highway connecting Los Angeles to San Diego was closed during the event by the California Highway Patrol. According to the agency, this stretch of highway is usually used by more than 80,000 people each day.
California Gov. Gavin Newsom’s office said the federal government notified him Saturday morning that the military planned to fire live artillery on the busy highway, prompting highway patrol officers to temporarily close the highway.
Last week, the military said no mortar shells would be fired over the highway and that the event would not affect any highways or roads. Military officials said all activities would be strictly limited to the training grounds at Camp Pendleton and would not affect public areas.
But on Saturday morning, the federal government requested that the state change electronic highway signs to read “LIVE GUNS ON HIGHWAY,” according to the California Highway Patrol.
U.S. Navy Landing Craft Airbags (LCAC) unload equipment on the beach as U.S. Marine Corps V-22 Ospreys and CH-53 Super Stallions fly overhead during America’s Marines 250 event at Camp Pendleton’s Red Beach Oct. 18, 2025 in Oceanside, California. The US Marines mark their 250th anniversary with a live amphibious assault demonstration titled “Sea to Coast: An Amphibious Force Review” and visits from Vice President JD Vance and Secretary of War Pete Hegseth.
Mario Tama/Getty Images
Highway signs throughout Southern California warned drivers that there was live fire in the vicinity of the highway around Camp Pendleton.
ABC News has reached out to the Marine Corps, Camp Pendleton and the Trump administration for comment.
For hours on Saturday, drivers in Southern California were stuck in traffic jams on the freeway or had to take long detours.
During that time, shrapnel reportedly rained down on the highway in the closure zone, according to the CHP.
Shrapnel from artillery rounds fired by the US Marine Corps during a celebration in front of Vice President JD Vance and Secretary of War Pete Hegseth detonated prematurely and struck a patrol car, the California Highway Patrol said.
California Highway Patrol
In a police report obtained by ABC News, the CHP says a patrol car was hit by shrapnel. That SUV had “an approximately two-inch by half-inch piece of shrapnel on the hood of the patrol car,” according to the report.
The agency says in the report that shrapnel made a dent in the hood.
Additionally, patrol officers stated that an officer working the highway closure heard “what sounded like ‘pebbles’ falling onto his CHP BMW motorcycle.”
Shrapnel from artillery rounds fired by the US Marine Corps during a celebration in front of Vice President JD Vance and Secretary of War Pete Hegseth detonated prematurely and struck a patrol car, the California Highway Patrol said.
California Highway Patrol
CHP says it immediately alerted the Marine Corps that a mortar shell missed Interstate 5 and that shrapnel was falling around the highway. At that time, the Marine Corps, according to the CHP, immediately canceled the release of additional live ammunition over the highway.
A safety sweep was conducted on the highway for more shrapnel, but none was found.
Camp Pendleton officials told Fox News Digital that an investigation has been launched to determine the root cause of the incident. “The rally underwent a rigorous security assessment and deliberate layers of redundancy to ensure the safety of fellow citizens,” the statement to Fox read in part.
In response to the apparent premature detonation and firing of munitions onto the highway, Newsom wrote in
The California Highway Patrol said it is requesting a further review with the federal government to discuss public safety.
