CHARLESTON, W.Va. (AP) â¿¿ The federal Mine Safety and Health Administration says 10 miners died in work-related accidents at the nation's mines during the first quarter of 2012, and half of those occurred on five consecutive weekends. MSHA chief Joe Main said Wednesday that three of those killed on the five weekends were mine supervisors. Six of the 10 deaths were in coal mines. The others were in metal and nonmetal mines. Main says all fatalities are preventable with effective pre-shift and on-shift inspections that identify and correct hazards. He says better training will help miners recognize those hazards and know how to fix them. Last month, MSHA sent an accident-prevention alert to the mining industry after four consecutive weekends of mine fatalities. But the very next weekend, a fifth person died.