Al Jazeera has received pictures that purportedly show Libyan army officers killed for refusing to fire on the rebels, evidence of how Gaddafi deals with "traitors".
It is claimed the soldiers refused to shoot rebels in the mountainous region west of the capital, Tripoli. The pictures were sent to Al Jazeera by a rebel group in the area.
A survivor of the killings says the men were rounded-up, their legs tied before being shot in the head or back from close range.
It is impossible to independently verify the authenticity of the video.
The pictures emerged as rebel fighters face perhaps their greatest challenge yet as they take stock of what seems a slowing of momentum in their campaign.
Libyan state media has also reported that a rebel base was recaptured by the army in the western city of Az-Zawiyah.
There are also reports that tank shelling of the city on Monday has been the fiercest so far. This comes despite earlier claims that the military had taken full control.
Rebels are regrouping in towns in the east of the country. The military and pro-Gaddafi forces have at least for the time being halted their advance to the Libyan leader’s home town and stronghold of Sirte.
A report on Libyan state television showed pictures it said were of rebel fighters killed in battle. A man describes the dead bodies as "rats serving a foreign conspiracy".
Al Jazeera's Charles Stratford reports.
Source: Al Jazeera