 -- Activists on two sides of the Syrian conflict both reported seeing what appears to be a drone lingering over Raqqa, Syria, near where U.S. special operations forces attempted to rescue ISIS hostages in July.

Undated images of the unmanned aerial vehicle (UAV), shot by Syrian activists as well as ISIS supporters, appeared on social media today. One former and two current U.S. officials familiar with the American drone program told ABC News the aircraft appeared to be an unarmed Predator drone, likely on a surveillance mission.

Activists with the “Raqqa Is Being Slaughtered” campaign, who snapped some of the photos, told ABC News the drone spent about three hours flying over Raqqa city between noon and 3pm local time. These activists also reported seeing two purported ISIS fighters wearily watching the drone on a commercial street before taking off on a 4x4.

While it’s unclear who was in control of the drone, public records show the U.S. has air bases that operate UAVs relatively close to Raqqa, like at Incirlik Air Base in southern Turkey, just over 200 miles away. Late last month the officials revealed President Obama had given the OK for the U.S. to fly surveillance aircraft directly over Syria, according to The Associated Press. U.S. officials declined to comment for this report.

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Raqqa is a stronghold for ISIS and the same city near which two months ago the U.S. military launched a rescue mission for several hostages, including some Americans, held by ISIS. The mission went “flawlessly,” according to Secretary of Defense Chuck Hagel, except there was no one there to rescue. The hostages had been moved.

Former U.S. military officials recently told ABC News that while the first rescue attempt and its subsequent public acknowledgment may have cost the American commandos some element of surprise, another rescue attempt wasn’t out of the question.

The U.S. is also urgently seeking intelligence on potential military targets. U.S. officials told ABC News that while top ISIS leaders appear to be using encrypted communications to avoid being detected, surveillance at ISIS command centers has begun to produce a few possible leads.

“If the U.S. … has a drone or fixed wing aircraft with the ability to strike an ISIS target, especially a senior leader, they’ll do it now,” said Seth Jones, a terrorism expert at the RAND Corporation.

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