Rex Heuermann, the suspected Gilgo Beach serial killer who terrorized New York state across three decades, is now facing even more murder charges as he stands accused of killing 6 people over the decades. This comes as prosecutors announced two more charges that accused the alleged serial killer of two more killings.

Before the new charges, Heuermann was accused of killing four women whose bodies were discovered buried along the popular Long Island beach called Gilgo Beach. These two new charges accuse him of killing Jessica Taylor and Sandra Costilla. Police have long suspected that they were victims of men preying on sex workers.

While Taylor disappeared in 2003, Costilla had been missing since 1993, which means that prosecutors now believe Heuermann has been a serial killer for much longer than previously thought, according to the Associated Press.

The new charges came after police once again searched Heuermann's Massapequa Park, as well as a wooded area on Long Island tied to the investigation. New forensic methods were used and they managed to "match hairs found on or near the vicinity of both victims" to a DNA profile that matches the suspected Gilgo Beach serial killer.

As for his plea to those two new charges, Heuermann pleaded not guilty to both of them. He was soon ordered to be held without bail afterward, with his lawyer, Michael Brown, saying that his client is "obviously in a bad place in terms of the new charges."

Prosecutors, meanwhile, told the press that these additional charges should provide "some small measure of closure" for the families of the two victims.

New Evidence Shows Suspected Gilgo Beach Serial Killer Rex Heuermann Kept Blueprints of His Crimes

Suffolk County prosecutor Nicholas Santomartino revealed during the hearing that authorities have also found some disturbing content on Heuermann's devices. This includes a planning document that outlined his strategies to conduct his killings.

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According to CNN, his computer contained a Word document with a section called "body prep." This includes detailed steps to clean, dismember, and transport bodies. The document file also outlines how to dispose of a body, avoid apprehension, and not leave DNA evidence.

"This was a planning document used by Heuermann to methodically blueprint and plan out his kills with excruciating detail. His intent was specifically to locate these victims, hunt them down to bring them under his control and to kill them," explained Suffolk County District Attorney Raymond Tierney, adding that other pieces of evidence "revealed Heuermann's significant collection of violent, bondage, and torture pornography, currently dating back to 1994."

DNA Evidence Tied Rex Heuermann to the 4 Previous Murders

As TMZ noted, Rex Heuermann has already been accused of killing four other women before these two new charges were brought, as he stood accused of killing Amber Lynn Costello, Melissa Barthelemy, Megan Waterman, and Maureen Brainard-Barnes over a decade ago

The Gilgo Beach murders were discovered when authorities found the human remains belonging to 11 different people in the area between 1996 and 2011. Along them are the four women the alleged serial killer was accused of murdering.

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This article is owned by Latin Post.

Written by: Rick Martin

WATCH: Serial Killer Suspect Rex Heuermann Charged with More Murders - COURT TV