US Secretary of State Hillary Clinton has expressed her dismay at a video that appears to show American marines urinating on the dead bodies of Afghan Taliban fighters. Both the date and origin of the video are unknown.
Washington officials have ordered an investigation.
Clinton told reporters that there would be serious consequences for any soldier who had taken part in such acts.
“I want to express my total dismay at the story concerning our marines. Anyone found to have participated or known about or having engaged in such conduct must be held fully accountable,” she said.
The video comes to a light as the United States and its allies are trying to orchestrate talks between President Hamid Karzai and the Taliban.
The US has some 90,000 troops in Afghanistan, including some 20,000 Marines.
Efforts are being made to strike a peace deal with a view to international coalition forces leaving the country by the end of 2014.