The following video, posted on December 23rd 2012, shows the clearest view of the munition being launched
The below image shows the clearest view of the munition, and I've adjusted the levels on the image to make the shape as clear as possible.
As you can see this matches the unusual shape of the UMLACA. Below we see the launcher
This twin barreled launcher appears to be of the same type photographed in Aleppo in November 2012, shown below, with the second picture showing it apparently loaded with an UMLACA
We get a much clearer view of the launcher in the next two videos from Mezzeh airbase
Another two videos show what appears to be the same vehicle launching rockets from Mezzeh Airbase
With a sixth video showing a launcher with the same launch profile seen in the above videos
It seems there's an ever increasing body of evidence confirming the Syrian government are capable of launching the rockets used in the August 21st attack, and that they've been using those launchers since at least November 2012. These videos are from one location in Damascus, but we know there's at least one video showing an UMLACA launch from Qadam railway station in Damascus, so it might be time to revisit some old videos showing rocket launches, and giving them an extra close look.
More posted on the subject of the August 21st attacks can be found here, and other posts on chemical weapons and Syria, including extremely informative interviews with chemical weapon specialists, can be found here.
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