NEW YORK — Freezing conditions hit the US East Coast on Sunday after a rare October snowstorm and icy rain reportedly killed at least three people, sparked long airport delays and caused massive power outages.
The "historic early season" snowstorm wrought havoc on air, rail and road traffic from Washington to Boston, with the National Weather Service warning that travel at night would be "extremely hazardous."
One person died in Connecticut in a traffic accident caused by icy road conditions, local media reported.
In Massachusetts, a fallen power line electrocuted a man, and a tree that fell under the weight of snow killed a person in Pennsylvania, the reports said.
A total of two million people were without power in a storm zone stretching from the Mid-Atlantic to New England, MSNBC reported.
New Jersey Governor Chris Christie declared a state of emergency across his state "because of the severe weather conditions," he said on Twitter.
Nearly 500,000 customers were without power in New Jersey alone, he said, urging residents to "stay safe and off the roads."
Air travelers were seeing an average delay of six hours on flights to and from Newark International Airport, the Federal Aviation Administration said. Similar problems were affecting New York's Kennedy international airport.
Passengers at Philadelphia's international airport were experiencing delays of two and a half hours on average, the FAA said on its website.
Rail travel was also hit, with the Amtrak service between Philadelphia and Harrisburg suspended until further notice due to signal problems caused by the storm.
Christie said there were "significant closures and delays" on NJ Transit train lines due to downed trees on the tracks.
Forecasters issued a winter storm warning for large parts of the northeast, in effect until 6:00 am (1000 GMT) Sunday, predicting heavy snow, freezing temperatures and strong winds with gusts of up to 60 miles per hour (100 kph).
Nearly a foot (30 centimeters) of snow fell in parts of Pennsylvania, Connecticut and New Jersey, authorities said.
In Manhattan, where the storm marked the first October snow in decades, forecasters said up to 10 inches could fall.
In Maryland and West Virginia, some towns already had 10 inches on the ground as of 2000 GMT Saturday, the weather service said.
Unseasonably cold air was pouring into the northeast, and deep tropical moisture was set to surge northward along the east coast and "fuel an expanding area of heavy rain and snow."
Much of the region was hit by Hurricane Irene in August. Its heavy rains and wind killed more than 40 people, left millions without power, destroyed homes and caused record flooding.
The unseasonably cold and wet weather did not dampen the spirits of anti-Wall Street protesters camped out in New York and Washington.
"Snow, what snow? I've got a country to worry about," read a sign held by a woman at New York's Zuccotti Park -- the nerve center of the Occupy Wall Street movement.
"We're cold, we're wet -- cancel the debt!" chanted a few dozen protesters marching in downtown Washington.
At the White House, President Barack Obama and his wife Michelle did not let the weather ruin their annual Halloween trick-or-treating event. They handed out candy, cookies and dried fruit to area children wrapped in wet coats.
"Let's give out some candy," Obama said. "I know it's cold. ... It's not ideal out here."