A Marine Corp helicopter crashed in Southern California on Tuesday — and four service members were believed to be dead.

A Marine Corps Super Stallion helicopter crashed in the area of El Centro, Calif., around 2:35 p.m. during a routine training mission, according to KYMA-TV.

Four crew members were aboard the aircraft and were presumed to be dead.

The Naval Air Facility El Centro Facebook page said they were aware of the accident and would release information as it becomes available.