Reader Aliboy writes to say to say that the video at 12.59pm has been played on Syrian state TV, where it was billed as showing rebels throwing the bodies of government soldiers into the river.
Mona Mahmood and I have watched the video again and gone through the dialogue line by line. There is nothing to prove conclusively whether those throwing the bodies in the river are members of the security forces or protesters. However, at one point near the end, one of the men asks in reference to one of the bodies: "Is this a military man?" Some Syrian soldiers are known to have defected to the protesters, so this line seems to suggest the speaker is a member of the security forces and the body that of an anti-Assad activist.
If it was the other way round, would a protester ask about the body of a soldier: "Is this a military man?" It seems unlikely. In addition, so far the consensus is that in Syria the protests have been largely peaceful – there are no recorded incidents of brutal behaviour such as this being carried out by protesters. In contrast, state forces have so far killed an estimated 1,700 civilians