Freezing rain turned to snow last night and blanketed the Washington area with up to four inches of snow in some places, causing havoc on ice-slicked highways and sending salt trucks rumbling through the streets for the first time this season. In downstate Virginia, police blamed the storm for three deaths.

The snow was expected to taper off into flurries by this morning's rush hour, according to the National Weather Service, but colder temperatures today could keep some highways glazed with ice, and more snow is expected Thursday.

By midnight, Washington had about two inches of snow, most of which rapidly turned to slush. Snow was still falling and city officials and representatives of the D.C. Transportation Department were to decide early today how to deal with the slush-clogged streets. It would also be morning before decisions on opening schools and government offices would be made.

In Montgomery and Prince George's counties, a snow emergency was declared, meaning that motorists are required to have their cars equipped with chains or snow tires. Up to three inches of snow fell on those suburbs, and last night state and county police officers reported that the Capital Beltway and Interstate 270 were virtually impassable.

Traffic was chaotic through most of the night as the snow continued to fall. In Fairfax County, police spokesman Debra Godwin reported: "People are sliding into each other all over the county" and minor accidents were so numerous that police were only responding to those with injuries.

In Glen Burnie, Md., a small, twin-engine plane encountered difficulty in heavy snow last night and crash-landed along a major highway, according to state police in Anne Arundel County. Authorities said the pilot apparently escaped serious injury.

Virginia was the hardest hit, with five inches of snow in some Washington suburbs and eight inches farther west toward the Shenandoah Valley. Earlier yesterday, police blamed the snowstorm for the apparent exposure death of a hiker, 24-year-old Michelle Connerton, found in the Grayson Highlands Park in central western Virginia.

In a second storm-related death, police said two Virginia men were killed and three others were injured when their pickup truck skidded on ice-slick Virginia Rte. 10 at Chipenham Parkway near Richmond and collided with a tractor trailor. The dead men were identified as Harvey Lee Allen Jr. 36, and John W. Tomlinson, 39, both of Chesterfield.