Taliban took over Bagram Air Base on Sunday, where occupying forces began to set free inmates there at Pul-e-Charkhi prison, according to the BBC.

When U.S. handed over control of the base to Afghan forces in early July, CNN reported that between 5,000 and 7,000 prisoners, including “senior al Qaeda and Taliban figures,” were housed there.

Thousands of inmates, including former Islamic State and al-Qaeda fighters, were released from a prison on the outskirts of Kabul. Footage published by an independent Afghan news agency, which supports the Taliban, appears to show militants letting the inmates out.

In a call with senators on Sunday, Chairman of the Joint Chiefs of Staff Mark Milley said that instead of the original estimate that terrorist groups could use Afghanistan as a base to rebuild within the next two years, the new timeline could be sooner.

“Two takeaways for me,” a source who was on the call told Axios. “We’re gonna leave tens of thousands of people behind … and the timeline in terms of threats has accelerated.”

America entered Afghanistan 20 years ago because it was a haven for terrorists.

Secretary of State Antony Blinken on Sunday sought to downplay speculation that history could repeat itself, according to The Guardian.

“We have tremendously more capacity now than we had before 9/11. We are going to retain in the region the over-the-horizon capacity to see and deal with any re-emergence of a terrorist threat,” Blinken told CNN’s “State of the Union.”

However, some worry that the potential for terrorism is worse now than ever before.

“A Taliban-led Afghanistan that provides tech-savvy global terrorists safe haven to remotely recruit new followers is a different level of security threat than it was previously,” security expert Barry Pavel wrote for the Atlantic Council.

He cautioned that “a Taliban-controlled Afghanistan — which could be even more dangerous than it was in the 1990s, and in particular on September 11, 2001.”

In July, CNN reported that the prison at Bagram field had a couple of hundred criminals with the rest of the thousands of inmates being terrorists.

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