Four service members were aboard a Black Hawk helicopter that went down Wednesday evening near Joint Base Lewis-McChord in Washington state, the US Army Special Operations Command confirmed. The incident involved an MH-60 Black Hawk from the 160th Special Operations Aviation Regiment (Airborne), and officials are calling it an “aviation mishap” in a rural area near the base.

“The cause of the mishap is under investigation,” a spokesperson from the Army said, noting that details about injuries or fatalities have not yet been released. A US Army official described the situation as “developing” and emphasized that additional information would be shared as it becomes available.

Local law enforcement responded after the military reported losing contact with the helicopter. The Thurston County Sheriff’s Office said deputies were dispatched to the Summit Lake area, southwest of Tacoma, where they located what is believed to be the crash site. “We have been advised that the military lost contact with a helicopter in the area, and we are working closely with JBLM to deploy any resources needed to assist,” the office said in a social media statement early Thursday.

Summit Lake, located just west of the base, is a rural area that presented challenges for first responders. Military and local authorities are now coordinating efforts to secure the site, ensure the safety of personnel, and gather information to determine what led to the crash.

The investigation is ongoing, and officials have stressed that the priority is the safety and well-being of the service members involved. More updates are expected as the Army and law enforcement continue their work at the scene.