US blizzard: Residents braced for 'biggest snowstorm'

A "potentially historic blizzard" could dump up to 90cm (3ft) of snow on the US north-east coast, the National Weather Service has warned.

New York's mayor said the storm could be the city's biggest ever, telling residents to "prepare for the worst".

Heavy snowfall is forecast from Philadelphia to Maine, pre-emptively closing many schools and offices.

Nick Bryant reports.