Rockford firefighters check an overturned semitrailer that blocked U.S. 33, near Rockford, for more than six hours Thursday. Billy G. Groves, 73, of Troy, reportedly fell asleep shortly after 2 p.m. and drove off the road while traveling eastbound, according to Mercer County Sheriff's Office reports. The vehicle, which carried frozen food, overturned as Groves attempted to bring it back onto the pavement and slid several hundred feet before stopping.