The mayor of New York, Michael Bloomberg
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Bloomberg: 'Stay off the roads and away from windows'

The powerful storm, Sandy, now classified as a cyclone, is wreaking havoc along the east coast of the United States.

In New York, a quarter of a million people are without power; and emergency services are receiving 10,000 calls an hour.

Many roads are underwater and subways have been flooded by rising waters from the East River and Hudson River.

The mayor of New York, Michael Bloomberg, warned people only to call 911 in an emergency.

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