SAINT MARYS, Pa. (WJAC) — An investigation is underway after an explosion in Saint Marys on Tuesday afternoon. State Police Fire Marshal Greg Agosti said it happened on Trout Run Road just before 4:19 p.m. Officials said Saint Marys Ambulance, Crystal Fire Department and state police were called to assist. There were no reports of injuries or damage. Agosti said a device exploded along the road and they are investigating what type of device it was. He said they are concerned about the size of the device because it’s not something that is commercially available. Criminal charges are a possibility, depending on what the device is and who put it there.