A major ice storm in the central United States is blamed for the deaths of some 20 people since Saturday, as large parts of the country continue to face freezing rain, sleet and snow.

U.S. weather forecasters say nearly three centimeters of ice are expected to coat parts of the country Tuesday and cause major power outages and dangerous road conditions. Forecasters say the ice is capable of widespread and destructive damage as freezing rain moves eastward across Oklahoma and Kansas.

White House spokeswoman Dana Perino Tuesday expressed concern for families who have lost loved ones in the storm. President Bush declared an emergency for the state of Oklahoma Monday, ordering federal aid to help coordinate disaster relief efforts.

Many flights have been canceled and schools closed as ice brought down power lines and tree limbs and created dangerous conditions.

Some information for this report was provided by AP.