California Governor Gavin Newsom slammed the Trump administration ahead of the event, saying firing live ammunition on highways is dangerous.
Vice President J.D. Vance celebrates Marine Corps 250th anniversary at Camp Pendleton
Vice President J.D. Vance and Secretary of the Army Pete Hegseth attended an event commemorating the Marine Corps’ 250th anniversary at Camp Pendleton.
Scripps News – KGTV San Diego
A shell exploded prematurely during a demonstration at Camp Pendleton, showering debris on a California Highway Patrol vehicle, a move criticized before the event by California Gov. Gavin Newsom, who had shut down highways over concerns about shells being fired on busy thoroughfares.
Vice President J.D. Vance and Secretary of Defense Pete Hegseth attended an event commemorating the Marine Corps’ 250th anniversary. Ahead of the event, Newsom slammed the Trump administration, saying “firing live ammunition on busy highways is not only wrong, it’s dangerous.”
Although the Marine Corps said the demonstration was “in line with established safety protocols” and no roads would be closed, Newsom decided to close a 15-mile stretch of Interstate 5 that divides Camp Pendleton, a major connection between coastal San Diego and Orange counties.
During the demonstration, “the shell failed to clear the road and exploded in flight near southbound Interstate 5,” according to a Highway Patrol report. The bullet was fired from Whites Beach at 1:46 p.m. local time and was one of about 60 planned by the Marines, according to the report.
Metal fragments hit a police car and a motorcycle. According to the report, the officer described hearing “a sound that sounded like a ‘pebble'” falling on the motorcycle. Officers found a dented, 2-inch-high piece of debris on the hood of the unoccupied police car.
The Highway Patrol reported the incident to the Marines, who ceased firing live ammunition. There were no injuries. Patrol officers cleared the highway and determined it was safe to reopen. It was closed from 11 a.m. local time to 3 p.m.
“This is an unusual and concerning situation,” Highway Patrol Border Division Chief Tony Coronado said in a press release. “It is highly unusual for live fire and explosive training activities to take place on active highways.”
A spokesperson for Vance referred questions to the Marine Corps. “We are aware of reports that a 155mm shell may have exploded in mid-air outside the designated impact area,” said Col. Gregory Dreibelbiss, commander of the 1st Marine Expeditionary Force.
“The demonstration went through a rigorous safety assessment and layers of intentional redundancy to ensure the safety of our compatriots,” Dreibelbis said, adding: “An investigation has been launched. We are fully committed to determining the root cause of the incident and applying its findings to future missions.”
Vance and his wife watched the demonstration while standing on top of a 7-ton military truck. It featured high-flying F-18s and F-35s, parachute drops, Navy SEAL landings, offshore destroyers and amphibious ships, a simulated village explosion, and an MH-60 helicopter dropping additional special forces at sea.
The Highway Patrol recommends “an after-the-fact review of planning, communication, and coordination among federal, state, and local governments surrounding the event.”

