By ROBERT BURNS

AP National Security Writer

WASHINGTON — U.S. Air Force B-2 bombers and drones attacked a pair of Islamic State military camps in Libya, seeking to eliminate extremists who had escaped the former IS stronghold of Sirte, the Pentagon announced on Thursday.

Pentagon press secretary Peter Cook said in a statement that the camps were located about 45 kilometers, or 28 miles, southwest of the central coastal city of Sirte.

The strikes were carried out overnight and were authorized by President Barack Obama, marking perhaps the final use of military force by a wartime president who intervened in Libya in 2011 as part of a coalition that ultimately toppled dictator Moammar Gadhafi.

Cook said the attacks were made in conjunction with the Libyan government of national accord. He did not say how many militants may have been killed.

“The ISIL terrorists targeted included individuals who fled to the remote desert camps from Sirte in order to reorganize, and they posed a security threat to Libya, the region, and U.S. national interests,” Cook said.

“While we are still evaluating the results of the strikes, the initial assessment indicates they were successful,” Cook added. “This action was authorized by the president as an extension of the successful operation the U.S. military conducted last year to support Libyan forces in freeing Sirte from ISIL control. The United States remains prepared to further support Libyan efforts to counter terrorist threats and to defeat ISIL in Libya.”

The Pentagon believes no civilians were killed in the strikes, a defense official said, while “several dozen” IS militants are thought to have been killed. The official was not authorized to discuss details of the attacks and so spoke on condition of anonymity.

Libya fell into chaos following Gadhafi’s ouster and killing. The country remains divided between east and west, with no effective government and a multitude of rival factions and militias.