An investigator looks inside the back of a charred transport van where six inmates died after the vehicle caught fire Thursday along I-40 near Dickson, Tenn., about 45 miles west of Nashville. The fire started after the fuel tank was apparently pierced by a broken portion of the drive assembly, investigators said. The driver and guard in the van were unable to save the prisoners, who were chained and shackled. The inmates, who were not identified, were en route to jails in the South.