RAPID CITY, S.D. — A B-1B bomber out of South Dakota’s Ellsworth Air Force Base crashed in a remote area of southeastern Montana on Monday but the four crew members survived, the U.S. Air Force said.

Col. Kevin Kennedy, commander of the 28th Bomb Wing, said the two pilots and two weapons system officers ejected from the aircraft before the bomber crashed near Broadus, Mont. He said the crew survived but there were some injuries.

“We are actively working to ensure the safety of the crew members and have sent first responders to secure the scene and work closely with local authorities at the crash site,” Kennedy said in a statement. “Right now all of our thoughts and prayers are with the crews and their families.”

Kennedy said the Air Force will conduct a thorough investigation to determine the cause of the accident, some 170 miles southeast of Billings, Mont.

The B-1 Lancer is a swing-wing bomber intended for high-speed, low-altitude penetration missions. Only Ellsworth and Dyess Air Force Base in Abilene, Texas, currently have B-1B crews.