A crash occurred yesterday (Wednesday) in Polk County leaving two people seriously injured. A 13-year-old Humansville male was headed eastbound on MO 123 and E 360th road, 3.5 miles south of Humansville, with a 7-year-old Humansville male occupant, on a 50CC dirtbike. He then failed to stop at a stop sign and was struck by a vehicle driven by 58-year-old Boliver Resident Bradley S Christian. Both juveniles were transported by air ambulance to Cox South. Christian was uninjured, and the bike was totaled. Neither juvenile was wearing a safety device.