The Corps said in a statement Tuesday that the accident at around 10 p.m. Monday also injured several with the 2nd Marine Division. The cause is under investigation.
The injured were taken to area hospitals for treatment and further evaluation.
The identities of those killed were not released pending notification of their families.
The Hawthorne Army Depot stores and disposes of ammunition. The facility is made up of hundreds of buildings spread over more than 230 square miles.