Pentagon officials believe that the militants are stealing equipment or buying it on the black market, the New York Times reported.
It is also possible that the equipment, which got into the hands of the Taliban, later goes to the militants of other terrorist groups and is used in conflict zones outside of Afghanistan, the sources said.
US command has been long restricting access to high-tech equipment and provided it to special forces exclusively, fearing it might be obtained by the militants because of corruption in Afghan army and police.
Night vision devices have been delivered to Afghanistan since 2016, and local security forces have not received the latest models. According to the documents cited by the newspaper, after the first assignment, the special forces returned only 161 of 210 devices. The cost of one device is estimated at $3,000.