The Taliban have captured major border crossings with Iran and Turkmenistan in a sweeping offensive across northern Afghanistan, officials say.
The militants say they seized two key border towns - Islam Qala near Iran, and Torghundi bordering Turkmenistan.
Video footage appeared to show Taliban forces taking down the Afghan flag from the roof of a border customs office.
The Taliban are rapidly retaking land across Afghanistan as the US-led mission removes the last of its troops.
Taliban officials say their fighters have taken control of 85% of territory in Afghanistan - a claim impossible to independently verify and disputed by the government.