A Virginia State Police trooper died yesterday of severe burns, two days after his car caught fire as he chased a driver apparently trying to evade a sobriety checkpoint in Cumberland County, state officials said.

They said Daniel Lee Williams, a retired U.S. Marine drill sergeant who became a state trooper in October 1998, died at 2:26 p.m. at the Medical College of Virginia Hospital's burn center in Richmond, where he was taken late Friday.

Williams, 38, was originally from Front Royal and moved to Farmville, in Cumberland County, when he was assigned to work there last spring, officials said.

The incident happened about 9 p.m. Friday, when the driver of a car heading toward a checkpoint on Route 600 near Farmville shut off his lights and drove into a field, said Lucy Caldwell, a state police spokeswoman.

Williams tried to catch up with the other driver. Minutes later, the trooper's car overturned, struck a tree and caught fire.

The driver Williams was pursuing has not been apprehended, Caldwell said. She said that officials are not sure what happened and that an investigation is continuing.

Williams was taken first to Southside Regional Medical Center in Petersburg and then flown by state police helicopter to the burn center in Richmond. On Saturday, doctors said he had only a 5 percent chance of survival, Caldwell said.

He is survived by his wife and three children younger than age 12.