The reported collision between two Marine Corps choppers carrying six crew members each happened just before midnight local time, Coast Guard spokeswoman Sara Mooers said on Friday.
The helicopters belonged to the Marine Corps Air Station at Kaneohe Bay, she said, adding that Coast Guard crews have spotted a debris field about 2.5 miles (four kilometers) off the north shore of Oahu but no people.
“They are currently searching for any possible personnel,” Mooers said.
The US Navy and a local fire department are providing assistance for the search operation, which has been hampered by dark, cloudy conditions and large waves of up to 15 feet, she said; Press TV reported.
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