Five Marines are dead after their military aircraft crashed in a remote, desert area of Southern California on Wednesday, authorities said.
The downed aircraft, an MV-22B Osprey, belonged to the 3rd Marine Aircraft Wing, which is based at Marine Corps Air Station Miramar in San Diego.
The Marines were taking part in a training mission when there was an "aviation mishap" near Glamis, the 3rd Marine Aircraft Wing said in a statement. There were no survivors.
"We mourn the loss of our Marines in this tragic mishap," Maj. Gen. Bradford J. Gering, commanding general of the 3rd Marine Aircraft Wing, said in a statement. "Our hearts go out to their families and friends as they cope with this tragedy."
The 3rd Marine Aircraft Wing identified the Marines who were killed in the crash on Friday. They included MV-22B pilots Capt. Nicholas P. Losapio, 31, of Rockingham, New Hampshire, and Capt. John J. Sax, 33, of Placer, California, as well as three tiltrotor crew chiefs -- Cpl. Nathan E. Carlson, 21, of Winnebago, Illinois; Cpl. Seth D. Rasmuson, 21, of Johnson, Wyoming; and Lance Cpl. Evan A. Strickland, 19, of Valencia, New Mexico.
The 3rd Marine Aircraft Wing said the crash took place around 12:25 p.m. local time, during routine flight training. An investigation into the crash is underway, the 3rd Marine Aircraft Wing said.
The Osprey was based at Marine Corps Air Station Camp Pendleton with Marine Aircraft Group 39.
The Imperial County Sheriff's Office and Imperial County Fire Department responded to the scene of the crash.
Naval Air Facility El Centro in Imperial County said it received reports of a downed aircraft near Highway 78 and Coachella Canal Road, and that military and civilian first responders were at the scene.
Reports of a downed military aircraft in the region came in midday Wednesday, according to Broadcastify audio obtained by ABC News.
ABC News' Matt Seyler and Alex Stone contributed to this report.
ABC's Alex Stone reports for ABC News Radio: