The Gilgo Beach serial killer suspect was linked to the crime scene with the help of a discarded pizza box that was thrown into a Manhattan trash can. Investigators running surveillance on Rex Heuermann at the Manhattan office where he worked as an architect watched him throw the pizza box away, according to court documents. The team grabbed a leftover pizza crust and had it swabbed and analysed by a forensics lab. Prosecutors say that the tested sample matched a mitochondrial DNA profile from a male hair collected off burlap recovered from the body of Megan Waterman. The DNA results came back on 12 June with a 99.96 per cent degree of accuracy, state court papers, with investigators stating that it “is significant that Defendant Heuermann cannot be excluded from the male hair recovered near the ‘bottom of the burlap’ utilized to restrain and transport Megan Waterman’s naked and deceased body.” Investigators refocussed on the Long Island serial killings last year and officials said on Friday that Mr Heuermann quickly became the focus of the investigation. “On March 14, 2022, the name Rex was first mentioned. A New York state investigator was able to identify him in a database and from that point on we used the power of the grand jury, over 300 subpoenas and search warrants, looking into this individual’s background to bring us to this day,” said Suffolk County District Attorney Ray Tierney. Eventually, DNA evidence and cell phone data would be used to charge Mr Heuermann with the murders of Melissa Barthelemy, Megan Waterman and Amber Costello. The 59-year-old pleaded not guilty to three counts of murder in the first degree and three in the second degree. Prosecutors say that he also remains the prime suspect in the killing of Maureen Brainard-Barnes, a 25-year-old Connecticut woman who went missing in July 2007. Her body was found near Gilgo Beach in December 2010 during the search for Shannan Gilbert. No charges have been brought in her case but officials say that the investigation “is continuing and is expected to be resolved soon.” Investigators also looked into Mr Heuermann’s Internet search history and say that he repeatedly searched for child sex abuse images, sadistic content, and images and information about his alleged victims. Prosecutors say that between March 2022 and June 2023, his email account was connected to more than 200 searches about his alleged victims, articles written on the investigation into their murders, as well as known and active serial killers. The searches included, “Why could law enforcement not trace the calls made by long island serial killer”, “Why hasn’t the long island serial killer been caught”, and “FBI active serial killers.” Read More Gilgo Beach murders – live: Rex Heuermann sobs in court hearing over Long Island serial killing How the Gilgo Beach serial killer turned the Long Island shore into a graveyard Long Island serial killer probe not over after architect is charged in 3 of 11 deaths Classmate of Gilgo Beach murders suspect reveals he left ‘love notes’ in her locker Manhattan architect, family man and accused serial killer: Who is Gilgo Beach suspect Rex Heuermann?