The US today urged Syrian rebels to uphold the international rules of war after a video emerged purportedly showing opposition fighters executing Syrian soldiers.

“We condemn human rights violations by any party in Syria,” State Department spokeswoman Victoria Nuland told presspersons.

“There is no justification for that kind of behaviour ever. Anyone committing atrocities should be held to account.”

The video posted on YouTube appeared to show about 10 soldiers being beaten, then lined up on the ground and executed with automatic rifles, after Thursday’s rebel attacks on checkpoints in the northwestern town of Saraqeb.

The UN human rights body said the video could be evidence of war crimes.

“At this point, on day one, all what (we) can say (is) it’s a very shocking piece of video,” Rupert Colville, spokesman for UN High Commissioner for Human Rights Navi Pillay, said in Geneva.

“If it is as it appears at this point, then it would be a war crime.”

The US has been backing the opposition in its bid to topple long-time autocratic leader President Bashar al-Assad, and Nuland recalled that “the Free Syrian Army themselves back in August put forward a code of conduct, which reflects rules of war, international codes.”

“They have routinely called on their fighters to adhere to that. And we would echo that sentiment here,” she added.

comment COMMENT NOW