COLUMBIA CITY — Columbia Township firefighters and Whitley County Sheriff's deputies are working to wrangle a tractor on the loose after its driver fell off and was run over and killed Friday afternoon.Crews were called to the area of a tree nursery on Keiser Road in southwest Whitley County at 12:15 p.m.The driver, whose name has not been released, was pronounced dead at the scene. The Whitley County coroner has been called to investigate. Police scanner traffic indicated that the tractor was going around in circles with no driver aboard.