FSA jihadists know that the Syrian Army won’t fire at civilians so because they’re losing the war, they’re using the fact as their last resort against the soldiers.
In this video, a civilian is playing a role of a street sweeper in order to make it look like he’s just engaging in a regular civilian activity so soldiers inside the patrolling BMP vehicle, which is stationed there to protect the civilians from raids by the terrorists, don’t suspect that something vile is being cooked behind those trees for them. Whether the sweeper was one of the FSA jihadists or a civilian coerced to play the role under a threat of death is unclear.
Once the premise of civilian activity in the FSA firing position is established, the sweeper gets out of the way and a terrorist with an RPG takes his place and fires at the BMP. Fucking terrorist scum.