RIVERHEAD, New York – Accused Gilgo Beach serial killer Rex Heuermann has been charged with a seventh murder: the death of Valerie Mack, whose remains were first found 24 years ago, according to a superseding indictment unsealed Tuesday.

The latest charges are one count of second-degree murder, according to a superseding indictment released Tuesday.

Mack, 24, had worked as an escort in Philadelphia and was last seen by her family in New Jersey this year.

On November 19, 2000, a hunter’s dog discovered some of Mack’s remains in a wooded area of ​​Manorville. The remains were in a black plastic bag wrapped with duct tape. Inside the bag were more plastic bags containing Mack’s decapitated body.

“In addition, both of her hands had been severed from her body above the wrists and the victim’s right leg had also been severed from her body at mid-calf,” said a bail application attached to the new charge sheet. “Mrs. Mack’s torso, legs and arms were also bound with rope.”

The rest of her remains were found more than a decade later, in April 2011, off Ocean Parkway near Gilgo Beach.

The New Jersey woman was identified through DNA. Like the other victims, prosecutors said she was also involved in sex work.

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Prosecutors named Heuermann, 61, a suspect in Mack’s death in June based on evidence allegedly found on an electronic device seized from Heuermann’s home in Massapequa Park on Long Island.

“Your honor, I am not guilty of any of these charges,” Heuermann said in court Tuesday, shackled in a suit and only a few moments before the judge.

Prosecutors said they linked Heuermann to Mack’s death in part through mitochondrial DNA analysis of a female hair found on Mack’s body. It matched the profiles of Heuermann’s wife and daughter, the bail application said. At the time of Mack’s murder, Heuermann’s daughter was probably between 3 and 4 years old.

Prosecutors said they also linked Heuermann to Mack’s death through evidence recovered from some of the 350 electronic devices seized from him, including his “significant collection of violence, bondage and torture pornography,” which at least dating back to 1994.

That online collection included images of breast mutilation and tying women with ropes, two things prosecutors say are consistent with the injuries to Mack’s chest and the way she was tied.

Investigators said they found a document they believe Heumerann used to “plan” his killings. The document was created in 2000, the year Mack was killed. Under the “Consumables” section, Heuermann allegedly listed “rope/string,” “saw/cutting tools,” and “foam drain cleaners.” Under a section labeled “DS,” which presumably stands for “Dump Site,” Heuermann allegedly listed one of the locations where Mack’s remains were found.

The document also included a section on “body preparation” with a note to “remove the head and hands,” according to the bail application. That has to do with the condition of Mack’s remains, prosecutors said.

Prosecutors said Tuesday that Heuermann kept newspaper and magazine clippings about the Gilgo Beach serial killings. This includes a People report, “Bodies on the Beach: Hunt for the Long Island Serial Killer,” which was found in a cardboard box shortly after Heuermann’s arrest in 2023.

In a more recent search in May 2024, prosecutors said they found a 2003 edition of the New York Post with an article headlined “Serial Killer Eyed in LI Slay” and a 1993 edition of Newsday with the headline ” Body discovered in Woods.”

“Rex A. Heuermann sought, purchased and kept these publications as souvenirs or mementos of his crimes,” prosecutors said.

Heuermann, who lived in Massapequa Park on Long Island with his wife and two children and commuted to an architectural firm in Manhattan, was arrested on July 13, 2023 and charged with the murders of Amber Lynn Costello, Megan Waterman and Melissa Barthelemy. He was charged with the murders of three other women – Maureen Brainard-Barnes, Sandra Costilla and Jessica Taylor – earlier this year. He pleaded not guilty to all charges.

The judge gave the defense until next month to submit evidence. The defense has questioned prosecutors’ DNA methods and may seek to limit its admissibility in court.

According to ABC News, they are also considering whether to ask the judge to separate the murder charge from others.

Heuermann remains held without bail.