Seven Marines and four soldiers were missing early Wednesday after an Army helicopter crashed during a night training exercise at Eglin Air Force Base in the Florida Panhandle.
The area where the crash happened Tuesday night was under a fog advisory.
The missing service members are all presumed dead.
The area was still extremely foggy Wednesday morning, which was affecting the search, Eglin public affairs specialist Sara Vidoni said.
Base officials said the Marines were part of a Camp Lejeune-based special operations group and the soldiers were from a Hammond, Louisiana-based National Guard unit.
The helicopter was reported missing at about 8:30 p.m. Tuesday, and search and rescue crews found debris from the crash at about 2 a.m. Wednesday, Eglin spokesman Andy Bourland said.
"At this time all are missing," Bourland said.
Names of those involved were not immediately released, pending notification of next of kin, he said.
Bourland said the Army helicopter took off from a nearby airport in Destin and joined other aircraft in the training exercise.
The UH-60 Black Hawk helicopter went down during a routine training mission on a remote swath of beach between Pensacola and Destin. The beach is owned by the military and is used for test missions.
The training area includes 20 miles of pristine beachfront that has been under the control of the military since before World War II. Military police keep a close watch on the area and have been known to run off private vendors who rent jet skis or paddle boards without permission.
Test range manager Glenn Barndollar told The Associated Press in August that the beach provided an ideal training area for special operations units from all branches of the military to practice over the water, on the beach, and in the bay.
The military sometimes drops trainees over the water using boats or helicopters, and the trainees must make their way onshore.
The Air Force base issued this statement about the crash:
Two UH-60 aircraft assigned to the Hammond, La Army National Guard were participating in a training exercise over night. One aircraft with four aircrew and seven Marines assigned to Camp LaJeune, N.C, was involved in an accident near Eglin range site A-17, east of the Navarre Bridge.
The helicopter was reported missing at about 8:30 p.m. March 10. Debris from the aircraft was located by search and rescue team at about 2 a.m. this morning. Search and rescue efforts are underway at the accident site currently.
The second helicopter and its personnel on board have returned and are accounted for at this time. The aircraft are assigned to the 1-244th Assault Helicopter Battalion in Hammond, Louisiana. They were participating in a routine training mission involving the Marine Special Operations Regiment from Camp LeJeune.
Names of the aircrew and Marines on board are being withheld pending [next of kin] notification. The accident is under investigation. Additional details will be provided as they become available.
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