BEIRUT: Thousands of new fighters joined ISIS in Syria last month in its fastest expansion to date, a body monitoring the war said Tuesday.
Now in control of roughly a third of Syria and large areas of Iraq, the Islamic State of Iraq and Greater Syria has been seizing territory from rival Islamist groups in a belt of territory north of Aleppo, threatening rebel supply lines into the city where President Bashar Assad’s forces are seeking to encircle the insurgents.
ISIS recruited at least 6,300 men in July, Rami Abdelrahman, founder of the Syrian Observatory for Human Rights, told Reuters – a big expansion from early estimates suggesting the group numbered around 15,000. Around a thousand of the new fighters were foreign, and the rest Syrian, he said, and while some had defected from other rebel groups, others had only just become fighters.
The surge followed ISIS’ rapid advance in northern Iraq in June, where its capture of the city of Mosul furnished it with new weaponry and resources, some of which were diverted to Syria.
Much of the recruitment has taken place in the ISIS stronghold of Raqqa. The city on the Euphrates river in northeast Syria has been the target of dozens of air raids by government war planes in recent days.
Anecdotal accounts have also suggested a rapid increase in the group’s numbers. “I can tell it’s not farfetched that ISIS gained thousands of new supporters recently with its operations in Deir al-Zor,” one Raqqa resident, an activist opposed to both the Syrian government and ISIS, told Reuters by Skype.
Deir al-Zor province is southeast of Raqqa and another area of ISIS control on the Euphrates river.
ISIS last week staged an advance westward in an area of territory it is seeking to control alongside the Turkish border. It seized several villages and towns north of Aleppo from rival Islamist groups in what observers believe is a push toward the border town of Azaz.
The Observatory said Syrian war planes Tuesday mounted airstrikes on ISIS positions in the town of Akhtarin, one of the areas its fighters seized in last week’s advance. No further airstrikes on Raqqa were reported.
Rebel brigades from insurgent-held territory in the northwest province of Idlib are now redeploying to meet ISIS’ advance toward Azaz, according to activists familiar with rebel movements.