A New York architect who was previously accused of four murders faced additional charges for two more deaths after prosecutors presented DNA evidence and a computer "blueprint" of the suspected serial killer's alleged crimes.

Rex Heuermann, aged 60, appeared in court accused of the murders of Jessica Taylor in 2003 and Sandra Costilla in 1993. Since 2010, authorities have been probing a series of at least 10 deaths on Gilgo Beach, Long Island. 

A "Blueprint" of Serial Killing

Suffolk County District Attorney Raymond Tierney revealed at a news conference that officials had discovered a document they believe the suspect used to blueprint his excruciating crimes meticulously.

Columns titled "problems" and "supplies" have outlined various aspects. Items listed under "problems" included "DNA," "tire marks," and "blood stains." Terms like "booties" and "police scanner" were found under the "supplies" column, as per court documents. Police suspect that two additional columns labeled "DS" and "TRG" indicated"dump site" and "targets," respectively.

Tierney disclosed that investigators had found the Microsoft Word document, dated 2000, on a laptop, which was divided into sections titled "pre-prep," "prep," and "post-event," which prosecutors interpret as a guide to planning the murders. The "post-event" section contained tasks like "change tires," "burn gloves," and "have a story set." A segment named "RECON" outlined steps for packaging a body for transport and listed items to dispose of after a murder. Another list labeled "body prep" instructed to "remove head and hands."

In his planning document, reminders included instructions to get sleep before hunting and guidance on attacking victims swiftly and quietly. Another note advised Heuermann to use push pins to hang drop clothes from the ceiling instead of tape. The document outlined lessons learned from previous murders and the most effective killing techniques researched by Heuermann.

A Total of Six Victims

One victim, Taylor, was discovered by the police in 2003 decapitated, her hands and arms below the elbow severed, and her body with a tattoo obliterated by a very sharp object.

Two hunters discovered Ms. Costilla's body in a wooded area of Southampton, New York, on November 20, 1993, with 25 sustained "sharp-force" injuries, including to her face, torso, breast, and genitals, which, according to court documents, were inflicted after her death. 

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Heuermann has been detained without bail since his arrest outside his Manhattan architecture office last July for the murders of three women: Melissa Barthelemy, 24, Megan Waterman, 22, and Amber Costello, 27. In January, investigators added new charges for the murder of a fourth woman, Maureen Brainard-Barnes, 25. The remains of these four women, believed to be sex workers, were found near Gilgo Beach in 2010.

Investigators confiscated numerous electronic devices from Heuermann's residence, which they suspect he utilized to communicate with the women, including computers, laptops, cameras, hard drives, mobile phones, and GPS devices. Analysis of these devices revealed a significant collection of violent, bondage, and torture pornography, which closely resembled the condition in which the two latest victims were found, according to Tierney.

Nearly 300 firearms were also discovered in his home. Recent DNA testing on male hairs found under Taylor's body and Costilla's shirt indicated a match with Heuermann. Investigators also noted that Heuermann's wife and children were absent from the state during five of the murders, providing him with ample time to plan his alleged crimes from their residence in the Massapequa Park neighborhood of Long Island.

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