[FoxNews] A U.S. Marine Corps helicopter crashed Tuesday -- killing its four crew members -- during exercises along the U.S.-Mexico border near Plaster City, Calif., military officials said."We are currently still responding to what we have confirmed as a single helicopter incident," said a Facebook post from the nearby Naval Air Facility El Centro.
The naval facility sent fire and security units as well as other helicopters to the scene of the crash, KYMA-TV reported.
The Marine Corps CH-53E Super Stallion helicopter reportedly belonged to the 3rd Marine Aircraft Wing in San Diego.
The Marine Corps was withholding the identities of those killed for 24 hours until next of kin notifications are complete.
"The status of all four is presumed dead pending positive identification," read a statement from the aviation unit.
The cause of the crash was under investigation. The crash would be the deadliest for the Marines since a July crash in the Mississippi Delta, which killed all 16 aboard.
Earlier Tuesday, a Marine Corps Harrier jet crashed in the East African nation of Djibouti. According to U.S. Naval Forces Central Command based in Bahrain, the pilot ejected shortly after takeoff and was in stable condition.