WASHINGTON, Feb. 24 (Xinhua) -- A powerful storm system on Wednesday hit the U.S. east coast after striking Gulf states on Tuesday, killing at least three people in Virginia and causing mass power outages across the region.

According to the National Weather Service, severe weather conditions could last into Wednesday evening and millions of people were somehow at risk.

"Strong winds throughout the atmosphere in association with this system will support rotating thunderstorms capable of producing tornadoes," said Ariel Cohen, a Weather Service forecaster.

The Virginia State Police said on Wednesday that three people were killed in a small town called Waverly, where a tornado left windows shattered and roads impassable.

Meanwhile, more than 10,000 homes and businesses in the Washington, D.C. area lost power and the National Weather Service had issued a tornado watch for the entire D.C. area nearly midnight.

On Tuesday, the storm system spawned about 10 tornadoes in southeast Louisiana, southwest Mississippi and Florida, according to local TV station ABC13, killing at least three people and injuring more than 30 others.