WASHINGTON — The U.S. is rushing an aircraft carrier and other military resources to the Middle East after seeing Iranian troops and proxy forces making preparations for attacks against U.S. forces and interests in the region, a defense official told The Associated Press.

At the White House, National Security Adviser John Bolton said Sunday night that the U.S. was deploying the USS Abraham Lincoln Carrier Strike Group and a bomber task force to the U.S. Central Command region, an area that includes the Middle East. In a statement, he said the move was in response to “a number of troubling and escalatory indications and warnings,” but did not provide more details.

Bolton said the U.S. wants to send a message that “unrelenting force” will meet any attack on U.S. interests or those of America’s allies.