The cause of the crash is under investigation.
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The Naval Air Facility in El Centro sent its condolences to those impacted by the tragedy early Wednesday in a Facebook post.
The chopper went down near El Centro, California, Tuesday afternoon during what the Marines termed was a "routine training mission".
Four U.S. Marines were presumed dead, after a chopper went down in California. The names of the crewmembers will be withheld until 24 hours after their relatives are notified, the Miramar base said.
Maj. Morgan Frazer, a spokesman for the unit, said additional details about the crash were not available Wednesday morning.
"We ask that you continue to be patient with us as the situation unfolds". According to an Associated Press report, the crash is considered as the deadliest crash in the history of Marines since a KC130T transport plane crash, which took place back in July near the Mississippi Delta that left all 16 dead, who aboard to the plane.
The Sikorsky CH-53E Super Stallion is the largest and heaviest helicopter in the United States military. It is primarily used for used for minesweeping and transportation of cargo. In 2016, 12 Marines were killed after two of the Super Stallions collided mid-air off the coast of Hawaii. In 2005, more than 30 people died when another CH-53E helicopter went down in Iraq during a sandstorm, according to AP.
"No other injuries were reported to personnel on the ground nor damage to infrastructure at the airport", the statement added.