The driver of a tractor-trailer was killed yesterday morning in a chain-reaction crash among three rigs that spilled toxic liquid across Interstate 95 near Fredericksburg, shutting the southbound highway down through two rush hours.

Virginia State Police said they hoped to have at least one southbound lane open for today's morning rush, but rain last night slowed repairs.

The accident happened at 1 a.m. in Spotsylvania County, when the three vehicles, driving one behind the other, slowed for a partial road closure where the highway was being repaved. The accident was still under investigation, but somehow the third vehicle struck the first two, said state police Sgt. F.L. Tyler.

The crash shut down I-95 in both directions for eight miles between the Massaponax and Thornburg exits. Northbound lanes started reopening about 6:30 a.m. But southbound lanes, which experienced backups of 20 miles to Prince William County about 5 p.m., were not expected to be open until at least early today, Tyler said. Southbound traffic was rerouted onto Route 1.

Backups today shouldn't be as bad as last night, Tyler added, because most traffic in the mornings is northbound.

The drivers of the first two trucks, George Lee Mathews, 57, of Baltimore and Vladimir Karmanov, 36, of Quebec, were treated at Fredericksburg's Mary Washington Hospital and released. Officials gave few details about the driver who was killed, other than to say he was 41 and not from Virginia.

The dead driver's vehicle was carrying 14 275-gallon packets of highly toxic liquid herbicide, and three to five of the packets burst, Tyler said. Emergency officials who responded to the crash were also treated because of concerns about exposure, although none was reported hurt.

The highway, however, was contaminated, and the state Department of Environmental Quality said the road would be torn up yesterday to whatever depth the leakage reached and then repaved.

The section that was to be repaved was about 200 yards long, Bundy said. "We don't know how far down we'll have to mill; it just depends on how far down the chemical seeped."

The tractor-trailer crash on southbound Interstate 95 near Fredericksburg caused tie-ups elsewhere when traffic was diverted to Route 1 to circumvent a toxic spill.