Shrapnel from Marines anniversary demonstration detonates over California interstate and hits squad car, highway patrol says

By Susannah Cullinane, CNN

(CNN) — An artillery shell fired as part of the Marine Corps’ 250-year anniversary celebrations prematurely detonated over Interstate 5 in California Saturday, striking a patrol vehicle with shrapnel, according to the California Highway Patrol.

No injuries were reported from the incident, which took place in an area where the highway patrol had stopped traffic during the live fire exercise at Camp Pendleton, the agency said in a statement Sunday.

The Marine Corps was alerted and canceled the firing of additional live ordnance over the highway.

“This was an unusual and concerning situation,” California Highway Patrol Border Division Chief Tony Coronado said in the statement. “It is highly uncommon for any live-fire or explosive training activity to occur over an active freeway. As a Marine myself, I have tremendous respect for our military partners, but my foremost responsibility is ensuring the safety of the people of California and the officers who protect them.”

The live demonstration had sparked a back-and-forth between Vice President JD Vance, who spoke at the event, and California Gov. Gavin Newsom, who declared it unsafe and ordered the freeway closed.

The incident also comes as the Trump administration and the state of California have clashed over several high-profile issues, including the deployment of the National Guard to Los Angeles and congressional redistricting.

The Marine Corps said live-fire training was conducted at Camp Pendleton year-round to maintain combat readiness and precision.

“We are aware of the report of a possible airborne detonation of a 155mm artillery round outside the designated impact area during the U.S. Marine Corps Amphibious Capabilities Demonstration,” spokesperson Capt. Gregory Dreibelbis said in a statement to CNN on Sunday.

“The demonstration went through a rigorous safety evaluation, and deliberate layers of redundancy, to ensure the safety of fellow citizens,” he said. “Following established safety protocols, firing was suspended. No injuries occurred and the demonstration concluded as scheduled.”

The Marine Corps is investigating the incident, Dreibelbis said. Marines on the West Coast “are committed to our enduring and mutually beneficial relationship with the people of Southern California,” he said. “Their safety and confidence is invaluable.”

Highway Patrol said it filed an internal report with a recommendation to review the coordination between federal, state and local government around the event.

The Camp Pendleton demonstration, which the Marines called the largest in a decade in the continental US, involved fighter jets, helicopters, Navy vessels and live fire from a towed howitzer.

Gov. Newsom closed a section of Interstate 5 in Southern California ahead of Saturday’s demonstration, citing “extreme life safety risk and distraction to drivers.”

“Firing live rounds over a busy highway isn’t just wrong — it’s dangerous,” Newsom, a Democrat who has frequently sparred with the Trump administration, said in a statement.

Vice President Vance’s office disputed Newsom’s claim that the live rounds were dangerous, saying that the demonstration was “an established safe practice.”

“If Gavin Newsom wants to oppose the training exercises that ensure our Armed Forces are the deadliest and most lethal fighting force in the world, then he can go right ahead,” William Martin, Vance’s communications director, said in a statement to CNN. “It would come as no surprise that he would stoop so low considering his pathetic track record of failure as governor.”

In his remarks from Camp Pendleton, Vance — the first Marine to serve as vice president — spoke of his time in the military, saying, “I would not be here today, I would not be the vice president of the United States, I would not be the man I am today were it not for those four years that I served in the Marine Corps.”

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CNN’s Isabelle D’Antonio and Kaanita Iyer contributed to this report.