(ABC NEWS) -- At least seven U.S. Marines were killed and seven others were injured during a mortar firing exercise in Nevada, the Pentagon said.
The Marines were all from the 2nd Marine Division based at Camp Lejeune, N.C., and were training at the Hawthorne Army Depot 140 miles southeast of Reno, Nev., when a mortar exploded shortly before 10 p.m. Monday.
The injured were taken to area hospitals, according to a statement from the Marines.
Several defense officials say this incident did not appear to involve a round landing on the troops.
The mountainous desert terrain of the 230 square mile depot is used as a training location for special forces since it "provides a realistic simulation of the situation in Afghanistan," according to the depot's website. The depot is also used as a storage site for ammunition awaiting demilitarization.
"We send our prayers and condolences to the families of Marines involved in this tragic incident. We remain focused on ensuring that they are supported through this difficult time," Maj. Gen. Raymond C. Fox said in a statement. "We mourn their loss, and it is with heavy hearts we remember their courage and sacrifice."
The army is notifying families before releasing the identities of the soldiers who were killed and said the conditions of the seven injured Marines would be shared as information becomes available.
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