Which group destroy cities luda treasures and killed thousands in russia during the 13th century

The correct answer is Mongol Tartars. 
Their invasion of Russia happened in the 13th century, when they looted and destroyed many cities, including Moscow, Vladimir, Kiev, etc. As a result of their invasion, Russia had to be included into Mongol Tartar's Golden Horde empire, which lasted until the 15th century.

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