Oct. 19, 2025, 11:34 PM EDTBy Dennis RomeroSAN DIEGO — The Marines Corps has launched an investigation after the California Highway Patrol said shrapnel from an artillery shell, fired during a live-fire demonstration touted by the White House, struck a law enforcement vehicle.No injuries were reported when an artillery round “detonated overhead prematurely” during Saturday’s 250th anniversary celebration for the Marines Corps at Camp Pendleton, the highway patrol said.But at least one of its patrol vehicles, on hand to help stop and divert traffic on Interstate 5 through the base during the demonstration, was damaged, the highway patrol said in a statement Sunday.“This was an unusual and concerning situation,” CHP Border Division Chief Tony Coronado, who also identified himself as a Marine, said in the statement. “It is highly uncommon for any live-fire or explosive training activity to occur over an active freeway.”Capt. Gregory Dreibelbis, spokesperson for I Marine Expeditionary Force, said in a statement Sunday that officials “are aware of the report of a possible airborne detonation of a 155mm artillery round outside the designated impact area” during Saturday’s Marine Corps amphibious capabilities demonstration.Pictures from a CHP incident report show a black-and-white unit with a hood apparently pierced by shrapnel, as well as multiple munition fragments. The report indicated that the fragment on the hood measured around 2 inches by 2 inches. According to a CHP map, the vehicle was at Interstate 5 and Las Pulgas Road, nearly a mile north of the Red Beach demonstration along the northernmost coast of San Diego County, when it was hit. The highway patrol said shrapnel from live artillery, fired over Interstate 5 as part of the anniversary demonstration, struck a patrol vehicle.California Highway PatrolThe report said a motorcycle officer also found a fragment measuring about 1 inch by a half-inch near his own vehicle. The CHP said the strike happened as officers were temporarily halting traffic on the freeway so motorists would be out of harm’s way during the demonstration.California Gov. Gavin Newsom had been critical of the plan to fire live munitions over the interstate in the days leading up to Saturday’s celebrations, which were attended by Vice President JD Vance and Defense Secretary Pete Hegseth, who both gave spoke at the event. Newsom, a Democrat who has repeatedly sparred with the Trump administration, had criticized the potential impact of a temporary closure of the 80,000-vehicles-per-day Interstate 5, and he said state authorities were denied sufficient notice of a dangerous and “absurd show of force.”“This could have killed someone,” Newsom said Sunday on X.Asked for a response to the CHP’s report of a shrapnel strike, Newsom spokesperson Diana Crofts-Pelayo also pointed to a post on the X account for the governor’s office: “We love our Marines and owe a debt of gratitude to Camp Pendleton, but next time, the Vice President and the White House shouldn’t be so reckless with people’s lives for their vanity projects.”The White House did not immediately respond to a request for comment Sunday. In the lead-up to Saturday’s celebrations, officials within the Trump administration had characterized complaints about the live-fire demonstrations and consequent freeway shutdown as an overreaction. “Gavin Newsom wants people to think this exercise is dangerous,” William Martin, Vance’s communications director, said in a statement to The New York Times. “The Marine Corps says it’s an established and safe practice. Newsom wants people to think this is an absurd show of force. The Marine Corps says it’s part of routine training at Camp Pendleton.”Dreibelbis, the Marine spokesman, said safety protocols were observed.“The demonstration went through a rigorous safety evaluation, and deliberate layers of redundancy, to ensure the safety of fellow citizens,” he said, adding that live fire was suspended Saturday in accordance with safety protocols. The CHP said it wants to conduct a review and create better communication with federal officials. Dreibelbis said the Marine Corps has launched an investigation and wants to learn from the incident, as well.”We are committed to determining the incident’s root cause and applying findings to future missions,” he said.Dennis RomeroDennis Romero is a breaking news reporter for NBC News Digital.Elyse Perlmutter-Gumbiner, Bill Feather and Madeline Morrison contributed.