The militants are threatening to arrest or punish family members if they cannot find the people they are seeking, according to former Afghan officials, a confidential report prepared for the United Nations, and American veterans who have been contacted by desperate Afghans who served alongside them. Most spoke on condition of anonymity to protect friends and loved ones still hiding in Afghanistan.

The officials said the Taliban had been combing through records at the ministry of defense and interior and the headquarters of Afghanistan’s spy service, drawing up lists of operatives to search for. And there are more and more reports that the militants are exacting swift and fatal revenge when they are found.

One former interpreter for American Special Forces said he saw another man gunned down feet from him on the mere suspicion that he had worked with foreign forces.

In the southern city of Kandahar, video posted on social media last week by RTA, Afghanistan’s public broadcaster, showed dozens of bodies left by the road, many of them reportedly Afghan soldiers and officials executed by the Taliban. RTA itself is now in the hands of the Taliban.