(NewsNation) — Five Marines are missing after a helicopter failed to make it to the Miramar Air Station.

The U.S. Marine Corps confirmed a search and rescue mission has begun in coordination with civil authorities. Here’s what we know so far.

The flight

The Marines were flying a CH-53E Super Stallion helicopter on a routine training flight from Creech Air Force Base, located near Las Vegas, to Miramar, but the helicopter was reported overdue on Feb. 6, 2024 around 1:00 a.m.

Cal Fire reported a call coming in around 2:20 a.m. regarding the missing aircraft. Between 12:30 a.m. and 1:30 a.m. National Weather Service radar showed turbulent weather rolling into the San Diego area.

Search efforts

The San Diego County Sheriff’s Department, Civil Air Patrol and Cal Fire are assisting with the search and a command post has been set up off Interstate 8 near Pine Valley. The search is complicated by snow in the area.

The 3rd Marine Aircraft Wing confirmed the helicopter had been located by civil authorities at 9:08 a.m. Pacific time in Pine Valley, California.

The helicopter

The Super Stallion can carry up to 55 people and is primarily used to transport heavy equipment and supplies during on-shore and amphibious assault missions. The craft can lift up to 16 tons and can be refueled mid-flight.

CH-53E helicopters have been involved in other incidents. In 2014, CH-53E crashed while trying to land on a transport dock at sea, however, all 25 people on board survived. In 2016, two CH-53Es crashed into each other during a training exercise near Hawaii, killing 12 Marines. In 2018, a CH-53E crashed during training in California, killing four Marines.

The crew

The Marines are with the Marine Heavy Helicopter Squadron 361, attached to Marine Aircraft Group 16 with the 3rd Marine Aircraft Wing.

This is a developing story. Check back for more details.