(Reuters) -Five U.S. Marines were killed when their Osprey tilt-rotor aircraft crashed in Southern California during a training mission, the military branch said on Thursday.
The five Marines were on an MV-22B Osprey when it went down near Glamis, California, just north of the Mexican border around 12:30 p.m. PDT (2130 GMT) on Wednesday, the Marine Corps said in a statement.
"We mourn the loss of our Marines in this tragic mishap," Maj. Gen. Bradford Gering said. "Our hearts go out to their families and friends as they cope with this tragedy."
The names and ages of the Marines were not released.
The Osprey, which can take off and land like a helicopter and fly like a conventional winged aircraft, was stationed at Marine Corps Air Station at Camp Pendleton about 140 miles (225 km) west of Glamis.
Contrary to posts on social media and early radio calls from the scene by emergency responders, there were no nuclear materials onboard, said Corporal Sarah Marshall, a spokesperson for the 3rd Marine Aircraft Wing, which operates the aircraft, according to the Los Angeles Times.