WASHINGTON — The U.S. Air Force rushed over the weekend to return home its bombers stationed at RAF Fairford, a U.S.-run military air base in England used to strike Iran, in part because of reports of a threat of a possible Iranian drone attack against the base and the American aircraft, two U.S. officials said Monday.

The two officials who spoke Monday could not say whether the Iranian threat was imminent. A third U.S. official said the U.S. can deploy the bombers from anywhere, so it made sense to move them out of an abundance of caution.

The move from RAF Fairford also came in the wake of an investigation into a possible planned terrorist attack at the base.

A Defense Department official told NBC News that “all U.S. bombers that were deployed to RAF Fairford have re-deployed to their home stations in the United States.”

“U.S. Air Force bombers routinely operate around the world to support global force readiness and operational requirements,” the official said.

“The Airmen that operate America’s bomber force, including B-1s, B-2s, and B-52s, remain ready to deliver precision global strike capabilities — including through operations that launch and recover from the continental United States — anywhere, anytime,” the official added.

The rushed withdrawal of at least 12 bombers included several that had just arrived in the U.K. as part of a rotation to the air base, two Pentagon officials told NBC News.

Those officials said the hasty deployment back to the U.S. was not a response to a new or different threat to the U.K. base but rather part of the threat reporting that was already out there, without giving further detail.

The United Kingdom’s Defense Ministry declined to comment on the matter Monday.