Beirut - Horrific videos purportedly showing Syrian rebels throwing the bodies of postal workers off a roof and a man's throat being savagely cut have appeared online, raising fresh concerns about atrocities in the increasingly brutal conflict.
Three videos all showing apparent events in the province of Aleppo, including a bound man being repeatedly shot, were posted on YouTube on Monday but their authenticity could not immediately be verified.
Both sides in the 17-month conflict have been accused of human rights violations as reports of cold-blooded killings mount.
Syrian Observatory for Human Rights director Rami Abdel Rahman said that if the videos were confirmed, he strongly condemned such atrocities whoever was behind them.
Graphic footage showed a crowd of people shouting "Allahu Akbar" (God is greatest) as they gathered around several bodies on the ground before another three victims are seen being hurled from the top of the building.
The incident was said to have taken place in rebel-controlled Al-Bab near the northern metropolis of Aleppo and the victims were identified as postal workers, but it was not clear when it occurred.
Blood on the pavement
"These are the heroes of Bab city who are inside the post office," the man shooting the video said. When the body of one man was thrown to the ground, the crowd is heard shouting: "This is a shabiha," referring to the pro-government militia.
In another shocking amateur video, a blindfolded man, with his hands tied behind his back, struggled as a group of men forced him to lie down on a pavement in Aleppo.
As a group of men chanted "Allahu Akbar", the assailant forced what appeared to be a small knife repeatedly across his throat as his blood spurted onto the pavement.
And a third clip, purportedly shot in Aazaz, also in Aleppo province, showed a bearded man being hauled out of a car boot with his hands tied behind his back and pushed to the ground.
One man opens fire on him with a small pistol, only to be joined by another with a rifle. They shoot many times at the man, who dies face down in a field.
"If these videos are confirmed, such atrocities harm the revolution. They only benefit the regime and the enemies of the revolution," Abdel Rahman said.
Meanwhile, a pro-government Syrian TV station says one of its cameramen who was kidnapped three days ago is believed to have been killed, said an AP report on Monday.
The station said gunmen kidnapped the cameraman on Friday along with three other employees of the pro-regime Al-Ikhbariya TV.
A video surfaced online on Monday, showing the three surviving members of the team. They said they were being held by rebel forces, who were treating them well.
A man who identified himself as a rebel spokesperson also appeared in the video, saying the cameraman was killed in government shelling. The general manager of Al-Ikhbariya TV said they believe he is dead.
It was impossible to independently verify the events shown in the video.
In June, gunmen raided Al-Ikhbariya's headquarters, killing seven employees.