**A search is under way for nine people missing after a US Coast Guard plane and a military helicopter crashed off the coast of southern California.**The collision is believed to have happened 16 miles (27km) east of San Clemente Island.
A Federal Aviation Administration spokesman said a pilot reported seeing a fireball near the area.
The plane - reported to be a C-130 aircraft - is believed to have had seven people on board.
The Marine Corps said the other aircraft was an AH-1 Cobra attack type.
Coast Guard spokeswoman Allyson Conroy said the crash happened at about 1910 (0210 GMT).
Cpl Christopher O’Quin, a spokesman for the Miramar Marine Corps Air Station said the helicopter belonged to the 3rd Marine Aircraft Wing stationed at Camp Pendleton.
A number of helicopters and navy vessels are being used in the search.