The report, based on interviews with witnesses, relatives and friends of the victims, detailed the “summary execution or disappearance” of military personnel, police, intelligence agents and paramilitary militia who had surrendered to or were apprehended by Taliban forces between August 15 and 31. October.
CNN has not independently confirmed the allegations in the report.
In their statement on Saturday, the 21 countries, including the United States, Germany, Japan and Britain, said the alleged actions “constitute serious human rights violations and are contrary to the Taliban’s announced amnesty.”
“We call on the Taliban to effectively enforce the amnesty for former members of the Afghan security forces and former government officials to ensure that it is maintained across the country and throughout their ranks,” the statement said.
The countries called for a full and transparent investigation into the claims of Human Rights Watch.
“Those responsible must be held accountable,” read Saturday’s statement. “We will continue to measure the Taliban on their actions.”