BEIRUT: An al Qaeda splinter group in Syria pulled out of two provinces in the country's northwest on Friday and headed to its eastern strongholds after months of clashes with rival rebels, activists said.
The Islamic State in Iraq and Greater Syria (ISIS), a former al Qaeda affiliate, and competing insurgents have been fighting since the start of the year, killing over 3,000 people and undermining the revolt against President Bashar Assad.
On Friday, ISIS - which alienated many rebels by seizing territory and killing rival commanders - finished withdrawing from the Idlib and Latakia provinces and moved its forces toward the eastern Raqqa province and the eastern outskirts of the northern city of Aleppo, activists said.
The Britain-based Syrian Observatory for Human Rights monitoring group said the withdrawal was overseen by the Nusra Front, al Qaeda's acknowledged branch in Syria, making the two provinces "completely free" of ISIS forces.
ISIS, which draws strength from a core of experienced foreign fighters, was initially welcomed in many rebel-controlled areas because of its fighting prowess and reputation for being relatively free of corruption.
The group later alienated many residents with a drive to implement a strict interpretation of Islamic law, but has also maintained sympathy in some areas because of its reputation for keeping looting and thievery in check.
"There's been an uneasy calm on all sides" since the withdrawal of ISIS forces, one activist from Idlib province said. "Civilians aren't celebrating because ISIS had eliminated thieves and bandits."
The Observatory's director Rami Abdulrahman said ISIS had been weakened by clashes and defections in the areas it had withdrawn from, but still had control over Raqqa province and plenty of resources to draw on.
A video posted online on Friday showed two fighters touring what they said were abandoned buildings that had been used by ISIS as a court and a prison in a town in the Jebel al-Akrad region. One fighter said the withdrawal had happened peacefully after negotiations between ISIS and other rebels.
ISIS started off as a rebranding of al Qaeda's branch in neigbouring Iraq, but the parent organisation announced it was cutting ties with the group last month over its refusal to limit itself to fighting in Iraq.
The Nusra Front, al Qaeda's Syria branch, has occasionally clashed with ISIS but has also tried to broker truces between ISIS and rival factions and fought alongside the group against government forces in other areas.
The infighting has nevertheless further complicated a war that has killed over 140,000 people and forced millions to flee their homes. The war enters its fourth year this month.
In a separate incident, the Syrian army killed 20 militants in an ambush in Tel Kalakh, a village 40 km (25 miles) west of Homs, a military source told Reuters. Lebanon's Al Manar television channel also reported the incident.
The source said the attack happened near a customs checkpoint close to the border with Lebanon, about 4 km (2.5 miles) from the village.
Pro-government Twitter accounts said the militants had been trying to enter Lebanon's Wadi Khaled after fleeing the Sunni town of al-Hosn, but Reuters could not independently verify these reports.
The source also said Syria's army had reached the eastern entrances of Yabroud, a rebel-held town near the border with Lebanon where the military has been making recent advances.