Eleven presumed dead in US Black Hawk crash

The helicopter was first reported missing amid heavy fog on Tuesday evening at around 8:30 p.m. local time (01:30 UTC) and an intensive search was still underway Wednesday evening along the coast near the Air Force base in Eglin, Florida.

Human remains have washed ashore near the base, a military spokeswoman told Reuters news agency. A US military official speaking anonymously said the 11 service members on board were presumed dead.

"Today is a tough day for the Louisiana National Guard," General Glenn Curtis said during a televised news briefing following the crash. "This will remain a search-and-rescue operation until further notice," he added.

Seven marines and four helicopter crew members comprised the soldiers on board. The Marines were part of a special operations unit based at Camp Lejeune in North Carolina, while the four crew members were serving in the Louisiana National Guard.

US President Barack Obama spoke by phone with the soldiers' commanding officers and "expressed his condolences to the families, fellow service members and communities" of the missing soldiers.

The UH-60 Black Hawk helicopter was participating in a routine exercise near the base in Eglin about 50 miles (80 km) east of the city of Pensacola. A second Black Hawk was scheduled to take part in the same exercise, but did not.

The other helicopter "started to take off and then realized, I guess that the weather was a condition and turned around," Curtis said.

The crash would represent one of the deadliest training accidents for US military personnel in years. In February 2012, seven soldiers were killed in a helicopter collision during a nighttime training mission along the border of California and Arizona.

And in 2013, seven marines lost their lives during a live-fire exercise at a Nevada munitions depot when a mortar round exploded prematurely.

bw/gsw (AFP, Reuters, dpa)