Storm affecting US east coast as havoc persists in South

A huge winter storm is affecting the densely populated US north-east, after wreaking havoc in the South.

Across the typically mild South, more than half a million homes and businesses lack power, and thousands of flights have been cancelled.

The mammoth storm has affected people in about 22 states from Texas to Maine and caused at least 12 deaths.

The most crowded swathe of the US - between Washington DC and Boston - is braced for up to 8in (20cm) of snow.

A band stretching from North-eastern Pennsylvania through New York State's Hudson Valley and into New England could see 10-20in of snow on Thursday, the National Weather Service warned.

Airlines grounded more than 3,300 flights on Wednesday and have already cancelled at least 3,700 flights for Thursday, including more than half of those between New York and Washington, according to flight-tracking website FlightAware.com.