Crews searched Friday for 12 Marines missing at sea after two CH-53 helicopters apparently collided during an overnight training flight off the coast of the Hawaiian island of Oahu, authorities said.
Personnel from the U.S. Coast Guard, Navy, and Honolulu Fire Department looked for survivors seven miles offshore in increasingly poor weather conditions. Swells reached 16 feet, surf rose to 40 feet, and visibility extended to only one mile, the Coast Guard said.
“The Coast Guard is asking that people use extreme caution along the coastal area surrounding the wreckage site which stretches from Mokule’ia Beach to Turtle Bay,” guard spokesman Lt. Scott Carr said in a statement.
“We are urging people to stay out of the water and off the beaches due to debris that could pose potential risk and cause serious bodily harm,” he added.
Marine Commandant Gen. Robert B. Neller expressed hope.
“Thoughts & prayers are with our Marines & their families in Hawaii as search efforts continue. We remain Semper Fidelis,” Neller tweeted.
Earlier, searchers spotted a fire and debris field, including an empty life raft, about 2½ miles north of Haleiwa Beach, according to Coast Guard Chief Petty Officer Sara Mooers.
The aircraft were believed to have collided late Thursday off Oahu’s north shore, Mooers said. The Coast Guard received notice at 11:38 p.m. local time of the two downed helicopters.
Marine officials contacted the Coast Guard about the missing aircraft around 11 p.m. (4 a.m. Friday ET), Mooers said. A Coast Guard helicopter arrived shortly after midnight (5 a.m. ET), according to the agency.
CNN affiliate KHON in Hawaii reported that witnesses said they heard a loud boom over the water and saw a flash in the sky.
Six people were on board each of the two heavy-lift transport helicopters, according to Mooers.
The missing aircraft are assigned to Marine Heavy Helicopter Squadron 463, Marine Aircraft Group 24, 1st Marine Aircraft Wing, the Marines tweeted.
According to the unit’s website, it is stationed at Marine Corps Naval Air Station Kaneohe Bay, on the opposite side of the island from where the apparent collision occurred.
Participating in the search Friday were two Navy warships, Coast Guard Cutters Ahi and Kiska, a MH-65 Dolphin helicopter, a HC-130 Hercules airplane, a MH-60 helicopter, Honolulu Fire Department crews, and a helicopter rescue boat, officials said.
A high surf advisory is in effect for the north facing shore of Oahu where the search is being conducted, authorities said.
The Marine Corps are investigating the cause of the accident.