An American B-1B bomber crashed in Montana on Monday during a routine training mission, the Air Force said in a statement.
The crew of four ejected and injuries were reported although further details were not available.
The cause of the accident involving the unit from the 28th Bomb Wing near the town of Broadus was under investigation.
"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," said Col. Kevin Kennedy, the bomb wing's commander.
The B-1B has flown in both the Iraq and Afghanistan wars.