Story highlights The Free Syrian Army Sunday took back from ISIS the town of Dabiq, Turkish state media and a monitoring group say

ISIS named its English language magazine after Dabiq

(CNN) As ISIS awaits one major assault in Mosul, Iraq, the self-declared caliphate has lost its control of a symbolic stronghold in north Syria.

The Free Syrian Army, a Turkish-backed faction, on Sunday took back the town of Dabiq from ISIS, Turkish state media and a monitoring group said.

The Syrian Observatory for Human Rights, a UK-based organization, said it received reports that groups of ISIS fighters had withdrawn from Dabiq overnight.

Though ISIS forces left, Turkish security sources told Anadolu's reporter the recapture of Dabiq was the hardest part so far for Operation Euphrates Shield.

US Secretary of Defense Ash Carter welcomed news of the recapture of the town and congratulated the fighters involved. "This is more than just the latest military result against this barbaric group," Carter said in a statement. "Dabiq held symbolic importance to ISIL. The group carried out unspeakable atrocities in Dabiq ... and claimed it would be the site of a final victory for the so-called caliphate. Instead its liberation gives the campaign to deliver ISIL a lasting defeat."

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