Hurricane Sandy: NYC Mayor Bloomberg warns of storm surge

New York City's Mayor Michael Bloomberg, has warned people that Hurricane Sandy is a "massive storm" and the greatest danger posed is the coastal storm surge.

Authorities warned that high tides triggered by a full moon could create storm surges of up 11ft (3m), sending seawater surging through parts of lower Manhattan.

Hurricane Sandy is bearing down on America's most densely populated region, with storm surges and flooding forecast up and down the East Coast.

Thousands have been ordered to evacuate New York City and New Jersey. The storm could affect 50 million people.