WARNING - STORY CONTAINS GRAPHIC IMAGES
A grim scene in Aleppo.
Activists say at least 65 bodies have been found -- many apparently shot in the head with their hands bound.
The video could not be independently verified by Reuters.
Rights groups says the death toll could rise as high as 80. It is not clear who had carried out the killings.
Both sides have been accused of carrying out summary executions in a conflict which has claimed more than 60,000 lives.
