CAMP FOSTER, Okinawa — The Naval Criminal Investigative Service is probing a shooting that injured four U.S. servicemembers at Camp Schwab in northeast Okinawa, officials said.

No major injuries were reported, and all four are in stable condition, Marine Corps officials said in a statement.

The incident was reported to the Marine Corps Provost Marshal’s Office around 10:45 a.m. Thursday, the statement said. The incident, which involved a 9 mm pistol, appears to have been caused by negligence.

The Marines said they could provide no other details while the situation is under investigation.

“The Naval Criminal Investigative Service is currently investigating the incident,” the statement said. “There exists no evidence at this time to indicate this was an intentional shooting, or a result of anything other than negligence.”

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