LEXINGTON, Va. (AP) _ Billy Freeman was hauling lemons from Los Angeles to Boston when a truck following his tractor-trailer slammed into his rig, overturning the trailer and spilling its cargo of fruit.

``We were coming off a hill and it was slick but we came to a stop,'' Freeman said Sunday. ``Then, after that, slam! Bang! I thank God I'm here because there were some people who did not make it.''

Four people were killed Sunday after a series of crashes along northbound Interstate 81. At least 23 people, including Freeman, were injured.

State police attributed the multi-vehicle crashes to the slippery weather conditions and to excessive speeds.

``It was like a war zone,'' Danny Young, a tow truck driver who helped remove mangled cars from the scene, told The Washington Post. ``It was terrible.

The crashes started shortly after the morning rush hour while traffic slowed just south of Lexington. The original slowdown was for an accident on the bridge crossing the Maury River.

Within minutes, eight tractor-trailers and eight cars lost control, including a state police cruiser that had stopped for the first accident. The highway's northbound lanes were closed for almost 12 hours with traffic backed up as far as 20 miles.

``For a few moments it was scary not knowing if you are going to live or die,'' said Douglas Toy, Freeman's driving partner.

State police were withholding the names of the dead until relatives could be notified. State police Sgt. R.D. Ross said they included two people from Tennessee and two from Alabama.

Sixteen of the injured were treated at Stonewall Jackson Hospital in Lexington. All but one were released. That victim, a boy, was in stable condition, said hospital spokeswoman Beverly Fertig.

Two people were taken to Carilion Roanoke Memorial Hospital in Roanoke. One was in critical condition and one was in serious condition, a hospital spokeswoman said.

Of five victims taken to the University of Virginia Medical Center in Charlottesville, a man in his 20s was in critical condition and another man was in serious condition. A 9-year-old girl and a 7-year-old boy were in fair condition, and their mother was stable, said David Haugh, the hospital's night administrator.