The bus manufactured in 1998 veered off a San Joaquin Valley highway before dawn Tuesday and struck an exit sign post. Federal and CHP investigators are also checking the bus company's records and making detailed inspections of the damaged bus, the highway sign and the roadway to determine what caused the crash. Investigators are collecting medical records and lining up interviews with relatives of a bus driver in a crash that killed four passengers in Central California when the vehicle hit a highway sign post that tore through its frame, officials said Thursday. The bus was too old to have a computer that records the engine, telling investigators if the bus exceeded the speed limit of 65 mph. Investigators have not been able to interview the driver who remains hospitalized and unconscious, Accetta said.

Source: ABC News August 05, 2016 00:17 UTC