AG investigation nabs 4 accused of assembling, selling 'ghost guns' in Philadelphia Published AG Josh Shapiro PHILADELPHIA - The Pennsylvania Attorney General's Office has brought charges against four Philadelphia men who are accused of purchasing kits to build and sell untraceable firearms from a gun show in Berks County. Attorney General Josh Shapiro on Sunday said the transactions happened at the Morgantown Gun Show from Feb. 27-28. In two separate instances, suspects purchased multiple 80% receiver ready-made gun kits and returned to Philadelphia to partake in illegal gun manufacturing operations. Ghost guns typically start as "80% receivers" that are often sold in kits without background checks. They can be easily and quickly put together, lack serial numbers so they cannot be traced, and, once fully assembled, can operate as fully functioning firearms.