The man was shooting from a rooftop at unknown targets while protesters can be heard in the video released on Monday.
The shooter also targeted two security forces at the scene and injured one of them.
Syria has witnessed weeks of demonstrations that sparked violence in several cities, which has led to the death of scores of protesters.
Authorities have denied allegations that security forces are responsible for the deaths, blaming the violence on armed groups.
Damascus says the protests are organized by foreign sources and aim to destabilize the country.
Syrian President Bashar al-Assad said on Wednesday that his country was the target of a big plot from outside.
He said enemies have taken advantage of the people’s legitimate demands to create division and undermine Syria’s stability.
Meanwhile, Syrian officials have condemned what they call attempts by various Western-backed groups to divide the Syrian nation.
Assad has been the president of Syria for the past 11 years. He took office in 2000 following the death of his father Hafez al-Assad, who was the leader of the country for three decades.
