SAN DIEGO — Seven Marines were killed in a collision of two helicopters near Yuma, Ariz., during night training exercises, the Marine Corps said today.

Lt. Maureen Dooley with Miramar Air Base in California said the service members with the 3rd Marine Aircraft Wing were based at Camp Pendleton north of San Diego. The crash Wednesday evening involved an AH-1W “Cobra” and UH-1 “Huey” helicopter, she said.

The aircraft collided in a remote portion of the Yuma Training Range Complex.

“We’re still gathering a lot of details as the sun comes up,” Dooley said.

It will be at least 24 hours before the Marine Corps releases the names of those killed, she said.