Accused Gilgo Beach serial killer Rex Heuermann is now facing charges related to the death of a seventh woman, Valerie Mack, according to Suffolk County prosecutors. Mack, 24, disappeared in 2000, and her partial remains were discovered later that year in Manorville, New York. This development comes as investigators continue to analyze DNA evidence using advanced techniques, which the defense intends to challenge. Heuermann pleaded not guilty to all charges during a recent court appearance.

Heuermann's arrest in July 2023, outside his Manhattan office, followed a lengthy investigation sparked by the search for a missing woman near Gilgo Beach. This search ultimately led to the discovery of 10 bodies, including additional remains of Mack. Initially charged with the murders of Melissa Barthelemy, Megan Waterman, and Amber Costello, Heuermann now faces charges related to six other victims: Maureen Brainard-Barnes, Jessica Taylor, Sandra Costilla, and now Valerie Mack.

Valerie Mack (left) pictured with her sister, Angela. Mack, initially known as "Jane Doe #6," was identified through genetic genealogy. (Photo courtesy of Angela Mack)

Suffolk District Attorney Ray Tierney stated that while evidence suggests Heuermann's family was out of town during the other six murders, they currently lack specific information about their whereabouts during the time of Mack's murder. Heuermann's estranged wife, Asa Ellerup, maintains her innocence through her attorney and asserts she had no knowledge of the alleged crimes. She plans to attend the trial and reserve judgment until all evidence is presented.

An undated photograph of Valerie Mack, whose remains were found near Gilgo Beach and in Manorville. (Suffolk County Police Department)

Tierney indicated that Heuermann kept news clippings and conducted online searches related to his alleged victims. Similar to Taylor, Mack's remains were found in two different locations: near Gilgo Beach and in Manorville. Investigations in other states are also exploring potential links to Heuermann.

Rex A. Heuermann in court. (Newsday/James Carbone)

Map of body locations near Gilgo Beach. (Suffolk County Police)

Heuermann, currently held without bail, is accused of leading a double life: a seemingly ordinary architect by day and an alleged abuser of sex workers during his free time. Investigators reportedly found Heuermann's estranged wife's DNA at a crime scene, but believe it was transferred there by Heuermann. Heuermann's next court appearance is scheduled for January 15.