Istanbul, Turkey (CNN) -- The Syrian government blamed last Friday's rebel attack on an electric power station in downtown Damascus on "armed terrorist gangs" -- the same epithet it has used to describe the protest movement that erupted in the southern border city of Daraa more than a year ago. But the gunfire and explosions that echoed across the Syrian capital in recent days have underscored a turning point of sorts. The clashes shattered the notion that Damascus exists in a security bubble. Helicopters said to fire indiscriminately Syria experts say the battle for Syria's two largest cities -- Damascus and the country's economic capital, Aleppo -- has begun.
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Gunfire echoing across Damascus underscores a turning point of sorts
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Syria experts say the battle for the nation's two largest cities has begun
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Damascus and the country's economic capital, Aleppo, have seen armed clashes
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They've also seen peaceful protests including strikes by shopkeepers
Several days after last month's market strike in @placeholder, however, shopkeepers in several Aleppo commercial districts mounted a similar but smaller protest.