investigators had no proof that the shotgun and clothes dumped in the stillwater river belonged to their prime suspect, gregg myers. >> one of the things we suspected was that he probably sought out a firearm through a classified ad, which also means there's no atf paperwork to connect gregg to the firearm. >> on a hunch, investigators subpoenaed gregg's cell phone records and looked for any unusual numbers. >> detectives basically went through those records looking for individual numbers that stand out. >> two numbers belonged to individuals who advertised shotguns for sale in a local newspaper. one seller recalled making a sale that week. >> eugene adams advised detectives at that point, yeah, someone had called his number, came and purchased the shotgun from him. >> adams told investigators that a man who identified himself as gregg myers bought a 12-gauge winchester shotgun. adams identified myers' picture