Seven Marines and four soldiers are missing after an Army helicopter crashed during a night training exercise at Eglin Air Force Base in the Florida Panhandle.

UPDATE: Human remains have washed ashore near the Florida coast following the crash of a UH-60 Black Hawk helicopter carrying seven Marines and four soldiers, an Eglin Air Force Base spokeswoman says, while stating the military is still conducting a search-and-rescue operation in the area.

The seven Marines are 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 around 8:30 p.m. Tuesday and search and rescue crews found debris from the crash around 2 a.m. Wednesday.

The area where the crash happened was under a fog advisory. Eglin public affairs specialist Sara Vidoni says the Marines are missing: "At this time all are missing," 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 part of the beach between Pensacola and Destin. The beach is owned by the military and is used for test missions.

Names of those involved were not immediately released, pending notification of next of kin.