BEIRUT (AP) — A Syrian opposition monitoring group says Turkey-backed opposition fighters have begun an offensive under the cover of Turkish airstrikes to capture the northern Syrian town of Dabiq from the Islamic State group.

The Britain-based Syrian Observatory for Human Rights says the attack was preceded with intense shelling on Saturday.

Turkey-backed rebel commander Col. Abdul-Razzaq Freiji said participants of the Operation Euphrates Shield are bombarding Dabiq and the nearby town of Soran in preparation for an all-out ground offensive on the two areas.

The town of Dabiq is central to IS propaganda. The extremists, citing ancient prophecy, believe Dabiq will be the scene of an apocalyptic battle between Christianity and Islam. The group named its online magazine after the town, which it has occupied since August 2014.