More than half a million homes and businesses in the Washington metropolitan area and the states of Virginia and Maryland remained without electricity Monday, three days after a string of thunderstorms left at least 17 people dead.

The federal and local governments suspended activities, gave personnel a day off and intensified efforts to clean up the streets and repair damage.

The governments of Maryland, Virginia and the District of Columbia declared a state of emergency after Friday night's storm knocked down trees and power lines, caused flooding in some areas and damaged thousands of buildings.

North Carolina and New Jersey also suffered the onslaught of sudden, powerful storms this weekend, which raised the number of people without electricity to 2 million during a week of soaring temperatures that increased health risks for children, the ill and the elderly.

According to a CBS network report, 17 people have died up to now and one went missing in the storms.

Health authorities repeated their warnings Monday for people to protect themselves from the heat, while power outages in the U.S. capital and the surrounding area have come shortly before the massive Fourth of July celebrations. EFE