KABUL, Afghanistan – Human-rights activists and Western officials expressed horror Sunday at a video showing a young Afghan woman who had been accused of adultery apparently being shot dead in front of a crowd of jeering men in a village only about an hour’s drive from the capital of Kabul.

Authorities in Parwan province, where the NATO force has one of its largest bases, said they believed the images, shot in late June, were authentic, and vowed to pursue those who carried out the killing.

The Taliban movement issued a statement denying responsibility for the woman’s execution. Local offshoots of the Islamist movement often carry out harsh punishments without the specific approval of the group’s leadership council.

NATO’s International Security Assistance Force condemned the apparent killing, the latest in a series of gruesome attacks against Afghan women to be made public in recent months. The footage came to light on the same day that international donors in Tokyo were approving billions of dollars in development aid to Afghanistan — some of it conditional on a commitment to protect women’s rights.

The 120-second video, which was first obtained by Reuters and later distributed via YouTube, shows a woman in a white shawl kneeling in the dirt. She could not speak even a word in her own defense. She then crumples after apparently being shot dead at close range by a gunman before a crowd of more than 100 shouting men arrayed on a dusty terraced hillside.

The Parwan provincial governor, Basir Salangi, said it was believed that the incident had taken place June 23 in the village of Qimchaq, in Shinwari district. He expressed disgust at the events depicted, which were reminiscent of the harsh public punishments that were commonplace when the Taliban ruled Afghanistan before the U.S.-led invasion of 2001.

A provincial spokeswoman, Roshna Khalid, said the victim was a 22-year-old woman named Najiba. She said local police had swiftly reported the incident, and the video was now being treated as evidence.