LAS VEGAS (Reuters) - A mortar explosion at a U.S. Army munitions depot in Nevada killed seven Marines from Camp Lejeune, North Carolina, and injured seven other service members during a live-fire training exercise, military officials said on Tuesday.
A Marine Corps official said a 60mm mortar round exploded prematurely Monday night during training at the Hawthorne Army Depot in western Nevada. The cause was under investigation.
"The Marines were conducting live fire and maneuver training at the Hawthorne Army depot," Brigadier General Jim Lukeman told a news conference in North Carolina. "A mortar round exploded in the mortar tube, causing the deaths of seven and injuring seven others. We don't know yet what caused this malfunction."
The blast was among the deadliest such training accidents on U.S. soil in recent years. Last February, seven Marines were killed when two helicopters collided during an exercise along the California-Arizona border.
The Marines killed on Monday had been undergoing training for the past month at the Marine Corps Mountain Warfare Training Center in Bridgeport, California and at Hawthorne.
"This is part of the type of training that we do just to maintain a force in readiness," Lukeman said. "It's not specifically linked to a nearby deployment."
The U.S. Marines ordered a blanket suspension of the use of 60mm mortars pending a review after the blast, Marine Corps spokeswoman Captain Kendra Motz said in a statement.
The explosion's victims were airlifted to Renown Regional Medical Center in Reno with injuries that included penetration trauma, fractures and vascular injuries, said Stacy Kendall, a spokeswoman for the medical center.
Six Marines and a Navy sailor were wounded. Of those, six were in serious or very serious condition, while a seventh suffered minor injuries, Lukeman said.
The explosion occurred at close to 10 p.m. PDT (5 a.m. GMT Tuesday) during an exercise at the Hawthorne depot, about 92 miles southeast of Reno, said facility manager Russ Collier.
The identities of the dead and injured have not been made public, but will be released after their families are notified.
Defense Secretary Chuck Hagel was receiving updates on the accident, Pentagon spokesman George Little said, adding that the incident struck a nerve with Hagel, himself an infantry veteran of the Vietnam war.
"This brought back memories of a training accident when he was in the U.S. Army when two soldiers were killed in a training accident, so he takes these incidents very much to heart," Little said.
Nevada Governor Brian Sandoval and Senate Majority Leader Harry Reid of Nevada also expressed condolences.
Hawthorne Army Depot is a 147,000-acre site used for the storage and destruction of demilitarized ammunition. Its location in Nevada's isolated high desert is also considered an ideal training environment for Special Operations forces preparing for deployments to Southwest Asia, according to a U.S. military website.
The facility was established as a naval staging area for bombs, rockets and ammunition, and was used by the Navy during most of World War Two. It was transferred to the Army in 1977.
The accident came a week after a U.S. military plane assigned to a Washington state Naval Air Station crashed during a routine training flight, killing all three crew members on board.
Reporting by Chris Francescani in New York, David Alexander in Washington D.C. and Cynthia Johnston in Las Vegas; Writing by Chris Francescani and Steve Gorman; Editing by Paul Thomasch, Nick Zieminski, Leslie Gevirtz