A Syrian rights group on Saturday released videos of pro-regime fighters apparently killing prisoners and cutting ears from bodies, after a video showing rebels executing soldiers raised international concerns.
The Syrian Observatory for Human Rights, a Britain-based watchdog, said it had received the videos after the images of rebels appearing to beat and kill captured troops sparked an international uproar.
"These videos were provided by activists following the broadcast the day before yesterday of a video showing atrocities committed by the rebels," the Observatory's director, Rami Abdel Rahman, told AFP.
"The regime has committed war crimes and crimes against humanity since the first day of the revolution, but these crimes cannot in any way justify crimes by the other side," he said.
One video, which Abdel Rahman said was filmed in July in the northwestern Latakia region, shows a man in military fatigues brandishing a severed ear and a knife, laughing at the camera.
"Here is the ear of a dog -- we will teach them a lesson," the man says, referring to the rebels battling against President Bashar al-Assad's regime.
The video later shows seven mutilated corpses on the ground. Emerging from a group of fighters in military clothing, a man approaches one of the bodies and cuts off an ear, another man shouting: "Give his ear to the dogs!"
Another video, filmed in February in the southern Daraa province, shows fighters, some in civilian clothes and some in military uniforms, firing with automatic weapons at a group of men lying on the ground who they say are rebels.
"Here are the armed men, the dogs, the unclean!" one man shouts in the video.
Rebel forces faced widespread criticism after a video was released that appeared to show them beating and executing soldiers after attacks on Thursday on checkpoints near the northwestern town of Saraqeb.
The video, also released by the Observatory, showed about 10 soldiers being beaten, then lined up on the ground and executed with automatic rifle fire.
The UN human rights body said the video appeared to show a war crime and warned that "accountability will follow" for those who commit atrocities, while London, Paris and Washington raised concerns.
"If we want a new democratic Syria that respects human rights, we cannot be silent about any crime, no matter who the perpetrator," Abdel Rahman said.