BEIRUT — Fighters from the extremist Syrian rebel group the Islamic State of Iraq and Syria withdrew Friday from key positions along the border with Turkey in apparent preparation for an anticipated offensive against their positions by rival rebel factions.
The ISIS forces abandoned their positions in the strategic town of Azaz and at a major border crossing with Turkey in what appeared to be an effort to fortify their hold on the group’s power center in the eastern province of Raqqa. It also pulled back from the Mannagh air base north of Aleppo and from other nearby villages, the Syrian Observatory for Human Rights said.
The move came four days after a rival extremist group, the Nusra Front, threatened ISIS with retaliation over the suicide-bomb assassination of a key al Qaida figure and set a five-day deadline for ISIS to make concessions. Warfare between ISIS and most other rebel factions has killed more than 3,000 since rivalries broke into violence Jan. 3.
The Syrian Observatory, which is based in the United Kingdom but operates a network of informants in Syria, said it thought ISIS was preparing for a likely attack by Nusra when the deadline expires.
“Aleppo region is their weakest link,” the observatory said.
The seizure of Azaz six months ago was a major setback for the U.S-backed Supreme Military Council, an umbrella group of more moderate rebel brigades, which had used the nearby border crossing as a crucial supply and logistics link between Turkey and rebel-held portions of Aleppo. Islamist fighters looted warehouses of U.S.-supplied equipment, and the United States and Great Britain suspended assistance to the rebels.
Although the withdrawal was hailed as a victory for the moderate rebel alliance, witnesses said ISIS’ departure from Azaz and surrounding villages didn’t involve fighting. ISIS had issued statements earlier in the week that indicated it planned to pull its forces closer to Raqaa.
Some reports indicated that ISIS was in the process of taking control of border crossings closer to Raqaa but they couldn’t be verified.
“Azaz was too far west and surrounded by enemies. They could never hold it if Nusra attacked,” said a Western military attache in Beirut who closely monitors rebel movements. “ISIS knows it has to keep its lines between Turkey, Raqaa and Iraq open for resupply and movement of its fighters. Azaz only offered them access to Aleppo, so holding it didn’t make sense in the bigger picture.”
Prothero is a McClatchy special correspondent. Twitter: @mitchprothero