1,037 members of the Afghan security forces fled into Tajikistan and dozens more were taken captive on Sunday after Taliban fighters made advances in northern Afghanistan, according to Reuters.

Why it matters: The crossings, which were permitted by Tajikistan, came after the Taliban took over at least six key districts in the northern province of Badakhshan, which borders Tajikistan.

• Sunday's retreat was the largest confirmed by the Afghan government since the Taliban began its northern offensive, according to Reuters.

What they're saying: Afghan President Ashraf Ghani spoke with Tajikistan President Emomali Rakhmon on Sunday to discuss the escalating conflict in northern Afghanistan and Rakhmon's concerns with the crossings.

The big picture: Tajikistan is looking into setting up camps for potential refugees from Afghanistan, according to Reuters.

• The Taliban has rapidly gained territory in Afghanistan since the United States began its military withdrawal, which is expected to be fully completed by Sept. 11.
• The U.S. military departed Bagram Airfield, which was the center of its war to oust the Taliban and search for the al-Qaeda perpetrators of the 9/11 terrorist attacks, on Friday.
• U.S. intelligence community has warned that the Afghan government could collapse as soon as next year as the Taliban's battlefield offensive grows.

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