Army Gen. Martin E. Dempsey told Martha Raddatz, the network’s chief global affairs correspondent, that despite continued U.S.-led airstrikes to keep ISIL forces at bay, he is concerned the key Kurdish city could fall into ISIL jihadists’ hands.

“I am fearful that Kobani will fall,” Dempsey said, adding that he has “no doubt” ISIL will conduct horrific atrocities if they have the opportunity to do so.

ISIL is putting pressure on the city’s outskirts, and into the city itself, the chairman said. ISIL forces are becoming more adept with the use of electronic devices, he added, and are making themselves harder to find and identify. “They don’t fly flags and move around in large convoys the way they did. … They don’t establish headquarters that are visible or identifiable,” he said.

Dempsey said he spoke to his Turkish counterpart a couple of days ago about the conditions in Kobani, and he noted that Turkey has forces on the border that will prevent ISIL from making any incursions into their country. “But, of course, ISIL is smart enough not to do that,” the general added.

The coalition could do more inside Syria, Dempsey said. And while he has not been asked to set up a no-fly zone there, he added, such an action is a possibility.

“Do I anticipate that there could be circumstances in the future where that would be part of the campaign?” he asked. “Yes.”

ISIL forces have changed tactics since the United States began airstrikes, the chairman acknowledged, making targets harder to find and more difficult to hit. “They know how to maneuver and how to use populations and concealment, so when we get a target, we’ll take it,” he said.

ISIL fighters have been trying to overtake Baghdad since they invaded Iraq, Dempsey said, and because the jihadist army is blending into parts of the Sunni population that was disenfranchised under former Iraqi prime minister Nouri al-Maliki’s government, the Iraqi capital could come under indirect fire.

“Heretofore, … mostly the Iraqis have been successful in keeping ISIL out of range, but I’ve no doubt there will be days when [ISIL uses] indirect fire into Baghdad,” he said.

The chairman said it is critical to keep the Baghdad airport out of ISIL’s hands, noting that in a recent and violent clash over Baghdad, the United States called in Apache helicopters to help Iraqi forces.

“The risk of operating in a hostile environment is there constantly,” Dempsey said. “This is a case where you’re not going to wait till they’re climbing over the wall.”

While President Barack Obama has vowed to the American people that no U.S. boots will be on the ground in the fight against ISIL, the chairman said he doesn’t rule out the possibility, as he recently testified on Capitol Hill.

“There will be circumstances when the answer to that question will likely be yes,” he said. “But I haven’t encountered one right now. When [the Iraqi forces] are ready to go back on the offensive, my instinct is that will require a different a kind of advising and assisting because of the complexity of that fight.”

Dempsey emphasized that it takes time to deliver a campaign objective.