IS has 20,000-31,500 fighters in Iraq and Syria: CIA

"This new total reflects an increase in members because of stronger recruitment since June following battlefield successes and the declaration of a caliphate, greater battlefield activity, and additional intelligence," he said.
It comes a day after President Barack Obama vowed to expand an offensive against IS extremists, a plan which foresees new air strikes against IS in Syria, expanded attacks in Iraq and new support for Iraqi government forces.
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