A crash that started with a jackknifed semi resulted in a pileup involving 20-30 vehicles in Lewis County. The pileup began around 8 a.m. yesterday on U.S. 61, about 2 miles north of Canton. According to the Lewis County Sheriff’s Office, a semi-truck jackknifed on the slick roadway, triggering a chain reaction crash. U.S. 61 northbound remained closed until last night while tow crews worked to clear crashed vehicles, and traffic was diverted at Highway 16. The driver of the jackknifed semi was transported to the hospital.