02:11 - Source: CNN
Syria: Assad's frontline with ISIS

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More than 26,000 ISIS fighters -- and as many as 27,000 -- are estimated to have been killed in Iraq and Syria by the U.S. led coalition since airstrike operations began in 2014

U.S. officials had put the figure at roughly 20,000 toward the end of 2015

Washington CNN —  

More than 26,000 ISIS fighters – and as many as 27,000 – are estimated to have been killed in Iraq and Syria by the U.S. led coalition since airstrike operations began in 2014, a U.S. official told CNN.

The official emphasized this is an estimate only. U.S. officials had put the figure at roughly 20,000 toward the end of 2015.

The latest information is a sharp increase from about one year ago.

In March 2015, the estimate was more than 8,500 ISIS fighters had been killed since operations began, according to testimony from Gen. Lloyd Austin, head of the U.S. Central Command.