No one was killed Monday when a U.S. Marine Corps CH-53E Super Stallion helicopter with 25 sailors and Marines aboard crashed Monday at sea in the Gulf of Aden, U.S. Naval Forces Central Command officials said.

The Marine chopper crashed at 2 p.m. GMT as the pilot attempted to land aboard USS Mesa Verde. The 17 Marines and eight sailors were not seriously injured and all 25 are aboard the Mesa Verde.

Navy officials said the crash was not caused by "hostile activity." The Marines and sailors were returning from a training exercise in Djibouti.

The Super Stallion was assigned to the 22nd Marine Expeditionary Unit (MEU). The 22nd MEU is deployed with the Bataan Amphibious Ready Group.

-- Michael Hoffman can be reached at mike.hoffman@monster.com