The video, which appeared to have been uploaded to YouTube on Sunday 27 February, cannot be independently verified.
Over four minutes, it shows Saif Gaddafi – who, in the past, has been seen as the acceptable face of the Libya regime by the west – reassuring pro-Gaddafi forces that they will be supplied with the money and the weapons they need to beat protesters.
Through the video, he is armed, and gestures using his machine gun at several points.
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“Some people spread bad rumours. The enemy forces said the armed forces escaped and joined the troublemakers,” he says.
“So today go and show them that the armed forces are with Libya. I will tell you something. You will get the support – all the means, weapons and money. Everything is fine. We will win!”
I will send you arms and from tonight, we start. Saif Gaddafi to supporters
As he speaks, chants of “Only God, Gaddafi and Libya” and “People want Muammar” are heard, and the crowd curses Al Jazeera.
He concludes: “No one will need food from today. This is your country, go and show them. I will be leaving now and I will send you arms and from tonight we start.”