A Mitchell man pleaded not guilty on Tuesday to aggravated assault. 26-year old Alexander Bear Robe Hofwolt is accused of assaulting a 58-year old man at a residence on West 11th Avenue on the night of January 9th. Police found the man on the ground unconscious with several injuries. He was airlifted to a Sioux Falls hospital. Bear Robe Hofwolt was found in a parking lot on South Sanborn. He is also charged with obstructing a law enforcement officer. He faces 15 years in prison if convicted. Bear Robe Hofwolt will remain in custody at the Davison County Jail after a bond modification request was denied. A trial date was set in April.