Los Angeles: Four Marines were killed Wednesday in an accident at Camp Pendleton in Southern California, US, a press release said.
"A fatal incident occurred at approximately 11 a.m...during a range maintenance operation," Xinhua quoted a senior base official as saying in the press release.
The incident is under investigation, and no other details have been released.
"We offer our heartfelt prayers and condolences to the families of the Marines lost today in this tragic accident. Our first priority is to provide the families with the support they need during this difficult time," Brig Gen John W. Bullard, the camp's commanding general, said in a statement.
The camp said the identities of the deceased Marines will be released within 24 hours of the notification of their families.