WASHINGTON (AP) — In his first congressional testimony on the tumultuous U.S. withdrawal from Afghanistan, Defense Secretary Lloyd Austin is defending the military’s execution of a frantic airlift from Kabul.

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He also asserted on Tuesday that it will be “difficult but absolutely possible” to contain extremist threats in Afghanistan without troops on the ground.

Speaking alongside Austin, Gen. Mark Milley, chairman of the Joint Chiefs of Staff, cited “a very real possibility” that al-Qaida or the Islamic State group’s Afghanistan affiliate could reconstitute in Afghanistan under Taliban rule.

And he said that could present a terrorist threat to the United States in the next 12 to 36 months.

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