Our Hearts Go Out To These Brave Soldier’s Families

• Two U.S. Marine helicopters collided with each other off the coast of Hawaii.
• They were taking part in a nighttime training mission
• 6 crew were on each helicopter, so far none of the 12 have been found.
• The Coast Guard is investing the debris field for survivors along with a Navy helicopter crew and local firefighters.

The U.S. Coast Guard searched for two Marine helicopters early Friday after officials said the aircraft collided with 12 people on board near the Hawaiian island of Oahu.

Coast Guard District 14 told CBS News that its personnel arrived on scene to investigate a debris field that includes an empty life raft and fire on the water.

The CH-53E “Super Stallion” helicopters were from the 1st Marine Aircraft Wing from Marine Corps Base Hawaii. Each carried six people, Coast Guard Chief Petty Officer Sara Mooers told The Associated Press.

She said the debris field was 2 1/2 miles off the coast, near the town of Haleiwa.

The aircraft were taking part in a nighttime training mission, according to NBC News. It's unclear what caused the crash.

A Navy helicopter crew and local firefighters were assisting in the search, ABC News reports.

Fox News' Jennifer Griffin and The Associated Press contributed to this report.