At least three deaths have been blamed on a crippling ice storm that has been plaguing the Midwest over the weekend and it threatened to stay near or below freezing through Martin Luther King Jr. Day.

State Highway Patrol in Missouri said that two people were killed in separate accidents, while authorities in Oklahoma said another person was killed in a semi-truck accident.

Ice buildups of one-quarter to slightly less than a half inch were expected to continue into Sunday morning from southeastern Kansas to central Missouri.

Becky Allmeroth, a state maintenance engineer for the Missouri Department of Transportation, said ice is "the most difficult storm to fight."

"We are keeping up with the changing conditions, but it is a continual battle," she said of the department's around-the-clock scrambling to treat the glazed roads. "The precipitation is coming in waves, and we have to apply more salt."

Icy roads Saturday created dangerous conditions and travel headaches for many people who avoided authorities’ pleas to stay indoors except for necessary outings.

A slick roadway was suspected in a Missouri wreck Friday that killed a 33-year-old woman whose sport utility vehicle slid on an icy freeway overpass south of St. Louis and struck several trees. A separate accident, caused by icy roadways, killed another person, authorities said.

Later Friday, icy conditions were blamed for a pileup involving more than 20 vehicles in Wichita, Kansas, but no serious injuries were reported.

Interstate 40 in western Oklahoma was closed in two places because of wrecks, including the jackknifing of several semitrailers in icy conditions in Caddo County. The Oklahoma Highway Patrol told FOX 25 that one person died in a crash along eastbound I-40 near Mile Marker 78. Several jackknifed semis in the area forced officials to close down the road in both directions for a short time

The storm's onset prompted the NFL to move the AFC divisional playoff game between the Pittsburgh Steelers and host team the Kansas Chiefs to Sunday evening to allow more time to treat roads and parking lots at Arrowhead Stadium.

The game was scheduled to kick off at noon but now will start at 7:20 p.m.

Many residents had prepared for the storms by stocking up on bread, milk and other necessities and by buying flashlights and generators to have on hand in case power gets knocked out.

The Associated Press contributed to this report.