Excerpt from Al Jazeera:
Al Jazeera has received pictures that purportedly show Libyan army officers killed for refusing to fire on the rebels.
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.
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. (CONTINUED HERE)