Four U.S. Marines were killed Wednesday during an operation to clear a range of unexploded ordnance at Camp Pendleton, in southern California.
Officials have not released any details on the accident. They say they are investigating the cause.
The deaths come about eight months after a mortar explosion killed seven Marines during a live-fire training exercise in Nevada.
A military investigation determined human error was to blame for that accident.
Officials have not released any details on the accident. They say they are investigating the cause.
The deaths come about eight months after a mortar explosion killed seven Marines during a live-fire training exercise in Nevada.
A military investigation determined human error was to blame for that accident.
