(CNN) Taliban forces unlawfully killed 13 ethnic Hazaras -- including nine surrendering former government soldiers and a 17-year-old girl -- in Afghanistan's Daykundi province on August 30, according to a new investigation by Amnesty International.
Since the US withdrawal from Afghanistan and subsequent Taliban takeover there has been concern that long-persecuted ethnic and religious minorities, such as the minority Shia Hazara ethnic group, will be targeted as they were under previous Taliban rule.
Eleven of the victims of the August 30 killings were former members of the Afghan National Defence Security Forces, and two were civilians, Amnesty reports. The killings are said to have taken place in Kahor village, in the Khidir district of Daykundi province.
"The Taliban extrajudicially executed nine of the Afghan National Defence Security Forces after they had surrendered, killings that appear to be war crimes. Two civilians were killed as they attempted to flee the area, including a 17-year-old girl shot when the Taliban opened fire on a crowd of people," Amnesty said in a news release on Monday, citing eyewitness testimony gathered as part of its investigation.
Amnesty said it has verified images and video evidence recorded following the incident and laid out events in a timeline, beginning with the Taliban taking control of Daykundi province on August 14.
CNN cannot independently verify the investigation's findings.
CNN has contacted the Taliban for comment.
"These cold-blooded executions are further proof that the Taliban are committing the same horrific abuses they were notorious for during their previous rule of Afghanistan. They repeatedly violate the rights of those they perceive as their adversaries, even killing those who have already surrendered," Amnesty International's Secretary General Agnes Callamard said in the news release.
"The Taliban say they are not targeting former employees of the previous government, but these killings contradict such claims."