Twenty-two Marines were injured in a training exercise on the base in Twentynine Palms on Thursday.
Marines and sailors of 2nd Battalion, 3rd Marine Regiment, were participating in Integrated Training Exercise 2-15 when a fire extinguisher system in their assault amphibious vehicle inadvertently discharged, officials said in a news release.
Base hospital officials said the service members suffered from "inhalation exposure" during a large-scale, combined arms exercise.
Those requiring medical treatment are receiving care at local medical facilities and are currently in stable condition.
On Jan. 24, a helicopter crashed during a training exercise on the base, killing two Marine Corps officers.