UPDATE: Marine Who Died at Twentynine Palms was Struck by Bulldozer

A U.S. Marine from Chico in Northern California who died this week during training at the Marine Corps Air Ground Combat Center in Twentynine Palms was struck by a bulldozer, a Marine Corps captain at the base said Thursday.

Private First Class Casey J. Holmes, 20, was fatally injured Monday March 11 during a 28-day "integrated training exercise," USMC Capt. Nicholas C. Mannweiler said.

Integrated training exercises, also known as ITX, can include live weapons, artillery, armored personnel vehicles, tanks, aircraft, and other heavy machinery.

"PFC Holmes was struck by a bulldozer," Mannweiler said. A Naval Safety Center summary described the incident as a "bulldozer mishap." Further information was not available.

Holmes, a native of Chico, enlisted in the Corps in May 2012, joining the 3rd Battalion, 3rd Marine Regiment at Marine Corps Base Hawaii in October 2012, USMC Cpl. Reece Lodder said in a statement.

His personal decorations include the National Defense Service Medal and the Global War on Terrorism Service Medal, Lodder said.

"The Integrated Training Exercise is a 28-day exercise conducted here that prepares Marine units for deployment in support of global contingency operations," Mannweiler said Wednesday.

"It also provides pre-deployment training to battalions that will deploy to Afghanistan," Mannweiler said. "As battalions and squadrons progress through the training, they are required to integrate together as a cohesive team through shared planning, briefing, rehearsals, execution and debriefing. This interaction builds the inherent understanding that Marines need to possess in order to fight as a unified force."

Banning-Beaumont Patch covered a live weapons training exercise involving an estimated 500 members of the 2nd Battalion, 4th Marines at Twentynine Palms on Jan. 21.

"What you covered in January with 2/4 is ITX," Mannweiler told Banning-Beaumont Patch. "We're talking about the same exercise."

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