Four people were killed Sunday when a bus carrying Dallas Cowboys staffers but no players collided with a van on a northwestern Arizona highway. The fatalities were passengers in the van, Arizona Department of Public Safety spokesman Quentin Mehr said. The bus occupants were uninjured. "All on the bus came through OK with some bumps and bruises," Cowboys spokesman Rich Dalrymple said in an email. Dalrymple said the bus was only carrying members of the franchise’s staff but would not say how many. There were no players on board.