POTTSVILLE, Pa.—A collision involving more than 40 vehicles closed a portion of Interstate 81 in Pennsylvania and sent more than a dozen people to area hospitals on Monday, according to the Schuylkill County Office of Emergency Management. The crash in northeast Pennsylvania happened around 10:30 a.m. and John Blickley, the deputy emergency management coordinator for the agency, said officials believe a snow squall clouded visibility and likely contributed to the accident. About 40 vehicles including multiple tractor trailers were involved in the initial crash, he said. No fatalities had been reported to the Schuylkill County agency, but Blickley said emergency personnel from four different counties responded and took about 20 patients to area hospitals for treatment. The county coroner’s office did not return requests for information about any fatalities. Blickley said three tractor trailers carrying unknown cargo were on fire when emergency personnel responded. Smaller fires broke out out in …