U.S. military officials are closely watching social media and news reports that say ISIS believes it may soon come under siege in Raqqa, Syria, its self-declared capital.
"We have seen this declaration of emergency in Raqqa, whatever that means," Col. Steve Warren, the spokesman for the U.S.-led anti-ISIS coalition, told reporters Friday.
"We know this enemy feels threatened, as they should."
Media reports have indicated that ISIS is moving personnel around the city and trying to put up covers in certain areas to shield potential targets from airstrikes and ground attacks.