"Doctors didn't manage to save the girl, who was in extremely critical condition. I express my deep condolences to her parents," the mayor wrote.
At least 17 people sustained injuries in the hurricane that hit the Russian capital on Saturday, with 14 of them, including three children, having been taken to hospital, Alexei Khripun, the head of Moscow's Healthcare Department, told Sputnik.
Moscow was hit by a thunderstorm accompanied by strong winds and heavy rain on Saturday afternoon. The storm is set to intensify and reach its peak in the early hours of Sunday.
Bad weather has caused train disruptions, dozens of flights have been delayed.
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