The number of combatants fighting under the banner of the militant group Islamic State of Iraq and Greater Syria (ISIS) could be three times larger than intelligence officials previously believed, according to a new estimate from the Central Intelligence Agency.
The CIA estimates that ISIS, the Islamist terrorist group that has declared a caliphate in the large swath of Iraq and Syria which it now controls, “can muster between 20,000 and 31,500 fighters across Iraq and Syria, based on a new review of all-source intelligence reports from May to August, an increase from our previous assessment of at least 10,000 fighters,” a CIA spokesperson said. That estimate accounts only for individuals fighting with ISIS itself, not with any affiliated group.
The new estimate reflects a sharp uptick in recruitment over the summer “following battlefield successes and the declaration of a caliphate,” the CIA spokesperson said.
The CIA believes more than 15,000 foreign fighters from 80 countries—at least 2,000 of whom are Westerners—have traveled to Syria to join ISIS ranks. A dozen or more could be Americans, the CIA believes.
A U.S. intelligence official cautioned that the CIA’s estimate is not a precise figure and reflects a broad approximation based on limited intelligence. “The gap between the low and high points indicates there is uncertainty about the exact number of fighters in (ISIS),” a US intelligence official said. “Given the changing dynamics of the battlefield, new recruits, and other factors, it is difficult to assess the precise number of individuals in a terrorist group that is evolving and practices good operational security.”
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