A N.C. Highway Patrol trooper was struck by a vehicle yesterday afternoon while conducting a traffic stop in Madison County.  27 year old Trooper Matt Mitchell was taken to Mission Hospital with serious injuries. He was listed in critical condition early this morning. No other information on the extent of his injuries was available. Trooper Mitchell initiated the stop at 4:55 p.m. on U.S. 19 near Crooked Creek Road. Accident Investigators were questioning the driver of the vehicle that struck the trooper. Trooper Matt Mitchell has been with the Highway Patrol for about three and a half years.