Two people suffered serious injuries following a motorcycle crash in Madison County. It happened Tuesday night on County Road 300 N just east of County Road 375. Police arrived to find a motorcycle carrying a driver and passenger lying on its side in the middle of the road. There was no indication as to what caused the crash. The driver was identified as 55-year-old Stephen Knotts of Anderson; the passenger was 51-year-old Kellian Zapf of Daleville. Neither was wearing a helmet. Both are in serious but stable condition.