How ‘safe’ plan to fire munitions over I-5 went off the rails

It was supposed to be a boisterous event at Camp Pendleton celebrating 250 years of the U.S. Marine Corps that included a live simulation of a beach assault by sea and air.

The plan involved Marines firing high explosive rounds from M777 Howitzers — artillery used to launch shells in wars in Afghanistan and Ukraine — into designated ranges. Federal officials last week insisted it would be done with “all safety precautions in place” and said no public highways would be closed.

But California officials expressed fears about those live rounds being fired over Interstate 5, which runs between the beach where the “landing” was taking place and the rest of the sprawling military installation.

Then, on Friday evening, the Marines did a test run without notifying state officials, firing artillery rounds over the I-5, according to the governor’s office — all while motorists drove on the freeway. The California Department of Transportation captured the live fire on video.

Early Saturday morning, Gov. Gavin Newsom announced the closure that day of a 17-mile stretch of the interstate — from just south of San Clemente to just north of Oceanside — during the event, which an estimated 15,000 attended and included a speech by Vice President JD Vance.

Now, the California Highway Patrol is reporting that a cruiser parked on an onramp of Interstate 5 was hit by falling shrapnel after an artillery round exploded midair, far earlier than intended, forcing an early end to the artillery demonstration. Although no one was hurt, the revelations raised new questions about safety issues and whether it was wise to fire live munitions over a freeway during the ceremony.

The Marines announced it was investigating the incident.

Here is the chain of events that led to a tumultuous day of military pride, traffic gridlock and confusion:

Wednesday

A report was widely circulated saying the White House intended to shut Interstate 5 amid plans to shoot missiles from Navy warships into Camp Pendleton, the Marine Corps’ 125,000-acre base along the coast of northern San Diego County.

Gov. Gavin Newsom’s press office responded to the report on social media, calling the idea “an absurd show of force.”

Late Wednesday night, the Marine Corps posted a statement on X saying it intended to hold a “live-fire” demonstration on Saturday at Camp Pendleton and that no public highways or transportation routes would be closed.

“All training events will occur on approved training ranges and comport with established safety protocols,” the statement said, adding that the White House would film the demonstration to be included in a national primetime broadcast for Nov. 9.

A Ukrainian soldier hefts a 155 mm artillery shell to be fired toward Russian front-line positions in Ukraine’s Donetsk region on Jan. 23.

(Evgeniy Maloletka / Associated Press)

Thursday

The Marine Corps said no ordnance would be fired from a Navy ship to the shore. The demonstration would involve the firing of high explosive rounds from M777 Howitzers into designated ranges, the Marine Corps said.

The M777 Howitzer, used by the Marine Corps since 2005, uses 155 mm artillery rounds, meaning that each round has a diameter of about 6.1 inches. Each round weighs around 100 pounds.

An Associated Press story about 155 mm howitzers describes the artillery weapon as one of the most-requested munitions in the war in Ukraine. Each round is about 2 feet long and essentially a very big bullet, made of up a detonating fuse, projectile, propellant and primer.

U.S. Marines fire an M777 Howitzer at Camp Pendleton in California during a December 2019 exercise.

(Lance Cpl. Roxanna Ortiz / U.S. Marines)

The rounds can be configured for different uses: They can be packed with highly explosive material, use precision guided systems, pierce armor or produce high fragmentation, the AP said.

The M777 Howitzer generally has a range of 15 miles to 25 miles.

Newsom’s office said that the Marine Corps on Thursday confirmed that the exercise would be conducted on training ranges, as is done routinely at the base, but not over Interstate 5.

State officials had been weighing whether to close the freeway themselves — but by Thursday morning, amid the new assurances, they backed off of those plans.

That afternoon, however, the federal government directed the cancellation of Amtrak and Metrolink train service along tracks that run parallel to Interstate 5 through Camp Pendleton, according to Newsom’s office.

Friday

State officials observed the M777 Howitzers launch shells over Interstate 5 from Red Beach on Friday.

A spokesperson for the Marines later said the firing was part of a dress rehearsal.

“M777 artillery pieces have historically been fired during routine training from land-based artillery firing points west of the I-5 into impact areas east of the interstate within existing safety protocols and without the need to close the route,” the statement said. “This is an established and safe practice.”

The state also received a request late Friday from the event organizers that electronic bulletin boards along Interstate 5 read: “Overheard fire in progress,” the governor’s office said. (The wording actually seen on Saturday said, “Live weapons over freeway.”)

CHP Border Division Chief Tony Coronado later said in a statement that “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,” Coronado said.

The CHP is not aware of live fire occurring over Interstate 5 in the past, a spokesperson said.

Late Friday night, referring to a report that the military did, in fact, plan to fire live artillery over Interstate 5 after all, Newsom on X called the plans “a profoundly absurd show of force that could put Californians directly in harm’s away.”

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Saturday

Newsom’s office issued a statement early Saturday saying that state officials were informed by federal authorities that live-fire activities would occur at 1:30 p.m.

Newsom’s office and Caltrans announced that morning there would be a closure of a 17-mile stretch of Interstate 5 during the demonstration “due to safety concerns.”

Although the closure was brief, it led to jammed freeways, stretching the travel time between L.A. to San Diego to three hours, an hour longer than is typical.

“Firing live rounds over a busy highway isn’t just wrong — it’s dangerous,” Newsom said in a news release issued just after 7 a.m.

The White House’s Rapid Response Team on X criticized Newsom for closing the 5 Freeway. “Not only did nobody at the White House or the Marines ask him to do so, the Marines repeatedly said there are no public safety concerns with today’s exercises,” said the post, which went up just after 11 a.m.

At 12:51 p.m., a California Highway Patrol protective services detail escorted Vance to the Camp Pendleton event. After Vance arrived, the detail was ordered to wait at the Las Pulgas Road on-ramp to the southbound Interstate 5.

The CHP stopped I-5 traffic from just south of San Clemente to just north of Oceanside around 1:15 p.m.

At 1:46 p.m., an artillery round from the M777 Howitzer was launched from White’s Beach northward, according to a CHP incident report obtained by the Los Angeles Times. The report said that “an artillery round failed to clear the roadway and detonated midflight. … The explosion sent shrapnel toward” the CHP protective services detail.

A map shows the direction of ordnance that the CHP says detonated prematurely, dropping shrapnel on the I-5.

(California Highway Patrol)

An unoccupied CHP patrol vehicle was hit by metal shrapnel and was damaged. The shrapnel that struck the patrol vehicle was about 2 inches by 2½ inches. The shrapnel left what was described as a “small dent/scratch” on the vehicle’s hood.

A CHP motorcycle officer heard debris falling on his motorcycle and an area around 3 feet from him, and later found a piece of shrapnel about an inch in length and half an inch wide near the motorcycle. The motorcycle was not damaged.

No one was injured.

A live video feed of the demonstration showed Vance observing the demonstration with a view overlooking the shoreline. At one point, a rat-a-tat-tat could be heard on the microphone, and an announcer said, “Thuuunderrrr. The guns recoil. The earth shakes and 1-5-5 mm shell tears through the air. … Steel rain inbound.”

After a few more words, though, the announcer largely fell silent.

The CHP incident report said the Marines originally planned for about 60 artillery rounds to be fired over a period of five minutes, from 1:46 p.m. to 1:51 p.m.

But after the artillery round exploded earlier than intended, raining debris down on the CHP, “the exercise was terminated and no additional munitions were fired,” the incident report said.

In a statement to The Times, Capt. Gregory Dreibelbis, spokesperson for the First Marine Expeditionary Force, said the Marines had launched an investigation based on the report of the possible airborne detonation of a 155 mm artillery round outside the designated impact area.

“The demonstration went through a rigorous safety evaluation, and deliberate layers of redundancy, to ensure the safety of fellow citizens,” the statement said. “We are committed to determining the incident’s root cause and applying findings to future missions.”

Dreibelbis said Marines fire artillery at Camp Pendleton nearly every week. He said systems such as the M777 “are designed to fire over the heads of friendly forces to achieve effects on our adversary. We trust this system with our lives,” and that “Marines have safely and effectively employed this system in combat operations, such as in Syria.”

Newsom on X accused President Trump and Vance of putting “lives at risk to put on a show.”

“This could have killed someone,” he said.

The Marines said in a statement obtained by Fox News that it was looking into what happened.

“The demonstration went through a rigorous safety evaluation, and deliberate layers of redundancy, to ensure the safety of fellow citizens. Following established safety protocols, firing was suspended. No injuries occurred, and the demonstration concluded as scheduled,” the Marine Expeditionary Force Communication Strategy and Operations team said. “An investigation has been initiated. We are committed to determining the incident’s root cause and applying findings to future missions,” the statement added.