4. all found dead around 2009-2010. cell phone tower information was used to trace heuermann's whereabouts as well as burner phones he was that using to to allegedly contact his victims. a pizza crust was pulled from a garbage can outside of his office in january also lingered him to a male hair found on the burlap that was used to restrain naked corpse. prosecutors say he was also frequently searching for information about the murders online. >> in a 14-month period, he had over 200 severance pertaining to the gilgo investigation. not only were -- was he looking at investigative insight, he was looking, trying to figure out how is the task force using cell phones to try to figure out what's happening. >> and, jesse, it doesn't stop there investigators also say heuermann was looking up photos of his alleged victims as well as viewing torture porn.