WASHINGTON (AP) — The Pentagon says U.S. warplanes have made three more airstrikes against Islamic State targets near the Mosul Dam, including a machine gun position that was firing on Iraqi forces.

But as U.S. forces continue helping Iraqi forces try to reverse the group’s land grabs in northern Iraq, President Barack Obama faces a quandary over their haven in Syria.

Defense Secretary Chuck Hagel says the Islamic State militants can be expected to regroup, pulling back into Syria before renewing their offensive.

Obama has been leery of getting drawn into the Syrian civil war, but Joint Chiefs Chairman Gen. Martin Dempsey says at some point the militants’ Syrian sanctuary will have to be dealt with.

Islamic State fighters have effectively dismantled the border between Iraq and Syria, and Dempsey says a regional coalition will be needed to defeat the group. He adds that the Islamic State group “will only truly be defeated when it’s rejected by the 20 million disenfranchised Sunni that happen to reside between Damascus and Baghdad.”

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