Gilgo Beach Serial Killer Suspect Rex Heuermann Charged in Two More Murders After Twisted 'Planning Document' Uncovered

Long Island serial killer suspect Rex Heuermann, who was arrested last summer and accused of killing four young women near Gilgo Beach, has been charged with two additional murders, RadarOnline.com has learned.

On Thursday, a grand jury indicted Heuermann for the murders of 20-year-old Jessica Taylor in 2003 and 28-year-old Sandra Costilla in 1993.

Taylor disappeared while working as a New York City escort in July 2003. Her headless and handless body was discovered by a dog walker in a wooded area near Manorville later that year. Her skull, hands, and forearms were found along Ocean Parkway, just east of Gilgo Beach, in 2011, Daily Mail reported.

The remains of Costilla, who was from Trinidad and Tobago but lived in Queens, were discovered by hunters in a wooded area in Southampton in 1993, expanding the timeline of the murders by nearly two decades. Unlike the other victims in the case, Costilla was not known to be a sex worker, and her long-unsolved murder had not previously been associated with the investigation.

Investigators linked Heuermann to Taylor and Costilla's killings through DNA from male human hair found on or near the remains of both victims, according to prosecutors.

The new indictment follows exhaustive K9 unit searches of the woodland areas where the bodies were found and another search of Heuermann's Massapequa Park home that reportedly turned up books about serial killers and a hard drive containing a disturbing "planning document" for the killings.

The Associated Press reports that one section of the document, titled “BODY PREP,” includes guidance to “REMOVE HEAD AND HANDS,” as well as any tattoos and trace DNA, and to wash the bodies. Another section, “THINGS TO REMEMBER,” highlights the importance of sleeping properly “BEFORE HUNT,” using thick rope, and limiting noise to increase “PLAY TIME.”

Never miss a story — sign up for the RadarOnline.com newsletter to get your daily dose of dope. Daily. Breaking. Celebrity news. All free.

Heuermann, a 60-year-old architect who is married with two children, was previously charged with killing Melissa Barthelemy, 24, Megan Waterman, 22, Amber Lynn Costello, 27, and Maureen Brainard-Barnes, 25, between 2007 and 2010. All of them were petite sex workers whose bodies were dumped along a stretch of Long Island's Gilgo Beach.

He has pleaded not guilty to all counts and remains in jail awaiting trial. A date has not yet been set.