Islamic State could gather up to 31,500 fighters

WASHINGTON, Sept. 11 (UPI) -- The Islamic State terror group could gather between 20,000 and 30,000 fighters, the CIA said, up to three times what the intelligence agency previously estimated.

A CIA spokesperson, whose name wasn't reported, shared the new estimates with CNN.

IS "can muster between 20,000 and 31,500 fighters across Iraq and Syria," the spokesperson said.

"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 added.

U.S. President Barack Obama, in an address to the nation Wednesday, said U.S. forces would focus on destroying IS, which is also known as ISIS and ISIL.

"Our objective is clear: We will degrade, and ultimately destroy, ISIL through a comprehensive and sustained counter-terrorism strategy," he said.

Obama plans to send 475 service members to Iraq to combat the terror organization, though the troops will not be involved in ground combat.