Pentagon press secretary John Kirby confirmed Friday that “thousands” of Islamic State prisoners were freed after the United States handed over bases to the Afghan government.

The freeing of thousands of Islamic State prisoners is under scrutiny after an Islamic State suicide attacker killed 13 American service members and a number of Afghan and other nations’ civilians at a gate at the Hamid Karzai International Airport on Thursday.

Men, suspected of being affiliated with the Islamic State (IS) group, gather in a prison cell. (FADEL SENNA/AFP via Getty Images).

“I don’t know the exact number — clearly it’s in the thousands when you consider both prisons, because both of them were taken over by the Taliban and emptied,” Kirby said, speaking of prisons on Bagram Air Base and Kandahar Air Field that held ISIS prisoners.

He said the U.S. did not transfer the prisoners over to Guantanamo because the plan was to turn the prisons over to the Afghan National Security Forces:

That was part of the retrograde process, was to turn over these responsibilities. They did have responsibility for those prisons and the bases at which those prisons were located and as the Taliban advanced, we didn’t see the level of resistance by the Afghans to hold some territory or some bases and unfortunately, those were the bases the Afghans didn’t hold.

“Those responsibilities were turned over in accordance with the retrograde plan back in April,” he said.

April was when President Joe Biden ordered all U.S. troops to withdraw from Afghanistan by August 31. As the military continued its withdrawal, the Taliban began its offensive and succeeded in taking over the country in just 11 days by August 14.

U.S. President Joe Biden pauses while listening to a question from a reporter about the situation in Afghanistan. (Drew Angerer/Getty Images).

After the rapid takeover by the Taliban, Biden ordered 6,000 U.S. troops to Afghanistan and the region to evacuate American citizens, Afghans, and others out.

The 13 service members killed Wednesday were part of that evacuation mission.

Military officials say they are not sure if the Taliban — who the U.S. has been relying on to man checkpoints to the airport — allowed the ISIS bomber and additional attackers through.

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