Four crew members are presumed dead after a Marine helicopter crashed in Southern California. The CH-53E Super Stallion vehicle went down around 2:30 p.m. local time Tuesday “in the vicinity” of El Centro, close to the Mexican border. Officials have not yet named the victims or said whether they were all Marines, but confirmed the crash took place during a routine training mission. The helicopter was reportedly with the 3rd Marine Aircraft Wing out of Miramar air station in San Diego. The crash is believed to be the deadliest involving a Marine aircraft since a KC130T transport plane went down in Mississippi in July 2017, killing 15 Marines and a sailor.