WASHINGTON — Four US soldiers are believed to have died after an MH-60 Black Hawk helicopter crashed during a routine training flight in Washington state late Wednesday, the Army’s Special Operations Command confirmed.

The helicopter, carrying four service members from the elite 160th Special Operations Aviation Regiment, went down near Joint Base Lewis–McChord at around 9 p.m. local time (0400 GMT Thursday), officials said.

“Our hearts are with the families, friends, and teammates of these Night Stalkers,” Lt. Gen. Jonathan Braga, commander of US Army Special Operations Command, said in a statement.

Recovery operations are underway, and the names of the soldiers will be withheld until their families are notified.

Army officials said the helicopter disappeared from radar when air traffic controllers lost contact with it during the exercise.

The cause of the crash has not yet been determined. — Agencies