Capitol Hill
© Getty Images

A huge snow storm is blanketing 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 weather system has affected people in about 22 states from Texas to Maine and caused a dozen deaths.

The storm dumped more than 12in (30cm) of snow in the Washington DC region, before descending on New York.

Snow-covered streets were deserted during the morning commute in the nation's capital, where the federal government shut down its offices.

Ten to 20 inches of snow could fall from north-eastern Pennsylvania to New England on Thursday, said the National Weather Service.

Nearly 5,000 flights were cancelled by Thursday morning, according to airline-tracking website FlightAware.com.

Winter celebration cancelled

While temperatures at the Winter Games in Sochi, Russia, rose to 17C (63F), the US was shivering in bitter cold once again.

Ironically, a celebration of winter tourism in the village of Lake Placid, New York state, was cancelled because of the storm.

Described by the National Weather Service as an event of "historical proportions", it leaves in its southern wake a wreckage of snapped tree branches and power lines coated in as much as an inch of ice, motorways turned to car parks, road accidents and residents shivering in darkened homes.

Forecasters said it was one of the worst storms to strike Atlanta, the largest city in the South, since 1973.

President Barack Obama declared a disaster in the state of South Carolina and all northern counties in Georgia, opening the way for federal aid.

Firefighter's fatal fall

On Wednesday evening, the Federal Emergency Management Agency said it was moving supplies, including generators, meals, water, blankets and cots to an emergency centre in Atlanta.

Snow plough
© Reuters
Even a snowplough found itself in tough driving conditions in North Carolina

At least 12 deaths have already been blamed on the storm.

Three people were killed when an ambulance slid off a west Texas road, flipped over and caught fire.

Meanwhile, a firefighter died when an out-of-control vehicle knocked him off an icy highway bridge in Dallas, Texas.

A man in Georgia was killed after slipping and falling on a patch of ice.

Thousands of vehicles have been stranded on snow-shrouded motorways around Raleigh, North Carolina, with some people abandoning their vehicles.

Soo Keith, of Raleigh, left her office shortly after midday, but after two hours had only driven a few miles.

White House
© Reuters
White out at the White House
She told the Associated Press news agency she eventually abandoned her vehicle and continued on foot, arriving home four hours later.

"My face is all frozen, my glasses are all frozen, my hair is all frozen," said Ms Keith.

Residents of Georgia appeared to have heeded official warnings, with motorways in the state clear but with many people stuck at home without electric power.

"Thanks to the people of Georgia," Governor Nathan Deal said. "You have shown your character."

Mr Deal asked those waiting for power to be restored to be patient, saying he was hearing of "good response times" from the state's utilities.
Snow in New York City
© Getty Images
Umbrellas were no match for the storm in New York City
US Congress building, Washington DC
© AFP
A man on skis by the US Congress building, Washington DC
Chattanooga, Tennessee
© AP
Residents took to walking in Chattanooga, Tennessee
Run on grocery items in Georgia
© Reuters
The bad weather caused a run on grocery items, including milk, in Georgia
Schools closed
© AP
And schools were pre-emptively closed across much of the South