A US Black Hawk helicopter crashed off the coast of Yemen on Friday during a training mission and a search was under way for one US service member, the US military said.

US Central Command said in a statement that five other service members aboard the aircraft had been rescued after the crash, which took place about 20 miles (32 km) off the southern coast of Yemen at 7 p.m. (16000 GMT).

A US official told Reuters that the cause of the crash was under investigation.

“When the incident took place the helicopter was not very high above the water,” CENTCOM spokesman Colonel John Thomas said.

There have been a number of aviation mishaps involving US military aircraft in the past few months.

The US Coast Guard recently said that it had suspended its search off Hawaii for five Army aviators missing since their Black Hawk helicopter crashed earlier this month.

In April, a Black Hawk US Army helicopter crashed on a Maryland golf course, killing one crewmember and seriously injuring two others.

Last month, a military transport plane crash killing 16 service members including elite special operations forces in northern Mississippi.

Source: Reuters