The Central Intelligence Agency has more than doubled its estimate of the number of fighters the Islamic State could have in Iraq and Syria.
In a statement, an agency spokesperson said they believe the Islamic State, also known as ISIS or ISIL, "can muster" between 20,000 and 31,500 fighters in those two countries.
Earlier, the agency had estimated ISIS had at least 10,000 fighters.
"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," the spokesperson said.
Quoting analysts and unnamed CIA officials, CNN reports that the additional fighters includes members who have been freed from prison.
The network reports:
"More than 15,000 foreign fighters, including 2,000 Westerners, have gone to Syria, a CIA source told CNN on Thursday. The fighters come from more than 80 countries, the source said.
"It's not immediately clear whether these were primarily ISIS fighters or were dispersed among a number of groups fighting the Syrian government."
Of course, this news comes a day after President Obama outlined a broadening of the U.S. offensive against the Sunni militant group. In a prime time speech, Obama vowed to "degrade and ultimately destroy" the Islamic State through "a comprehensive and sustained counter-terrorism strategy."