Updated | At least 6 dead as 'bomb cyclone,' thundersnow wallop NE U.S.

At least six people have died and more than 4,000 U.S. flights have been canceled due to a massive winter storm hitting the East Coast, with heavy snow, gusty winds and the coldest air of the season.

State officials said three of the deaths occurred in North Carolina and a fourth happened in South Carolina, as the weather system barreled up the eastern coast.

Among those killed were two men whose pickup truck slid off a road and overturned into a creek Wednesday night, North Carolina Gov. Roy Cooper said at a press conference this morning. The storm has also caused hundreds of car crashes around the Tar Heel State, Cooper said.

Two people were killed in Virginia on Thursday, according to authorities. A 75-year-old man in Hampton was clearing snow from a business parking lot when he suffered life-threatening injuries from a snowplow, while a young girl was killed while sledding down a driveway in Chester, police said.

The girl slid into the path of a Toyota Tacoma as it drove down the street. She was hit and later died at the hospital as a result of her injuries, according to police. Her age and identity were not released.

Meanwhile, U.S. airlines canceled at least 4,020 flights within, into and out of the United States as of 5 p.m. today, according to airline tracking firm FlightAware. Most of the cancellations were in New Jersey, Boston and New York.

(ABC)