Tiffin Police Department is investigating a robbery at Denny’s, 315 W. Market St., early Friday morning. Lt. Mark Marquis of Tiffin Police Department said a man entered the back door of the restaurant and stole money from an office. There may have been an accomplice nearby, he said. Marquis said there were employees in the front of the business when the suspect entered the back of the building, but it was unknown if any patrons were in there. He said the amount of money taken was undetermined Friday evening. Marquis said while it was initially believed a weapon was involved, he did ...