Amateur video, said to be from Syria, reportedly shows an execution of captured government supporters in Aleppo by rebels from the Free Syria Army.
The pictures posted on the internet appear to show a bloodied almost-naked man surrounded by his excited captors, who then open fire.
The images and the information are impossible to verify.
The foreign-based Syrian Observatory for Human Rights said it was “vengeance” and a crime as neither international nor Islamic law authorised the execution of prisoners.
The same organisation backed rebel claims that they had attacked and, after a long battle, taken control of a police station in Aleppo – one of three said to have fallen into rebel hands.
Again the reports cannot be verified.