Rex Heuermann, the suspected "Gilgo Beach" serial killer, was charged on Tuesday in the death of another woman. In total, New York authorities have now charged Heuermann in the killings of seven women that occurred over the course of three decades.

Investigators have accused Heuermann of killing Valerie Mack, a woman who had been working as an escort and whose remains were found on Long Island in 2000. Heuermann pleaded not guilty in court, and a judge ordered him to be held without bail.

Suffolk County District Attorney Ray Tierney said at a news conference on Tuesday: “The lives of these women matter. We, as investigators, understand that. No one understands that more than the families."

The latest charges against the suspected serial killer

Heuermann, a 61-year-old father and former architect, was charged with second-degree murder in Mack's death. According to the Associated Press, Mack's skeletal remains were first discovered in Manorville, N.Y., but more of her remains were found near Gilgo Beach over 10 years later.

The remains were identified through genetic testing in 2020. In a court filing, prosecutors said that a human hair found on Mack's remains likely belonged to Heuermann's daughter, who would have been 3 or 4 years old at the time of Mack's death and is not accused of any wrongdoing.

Heuermann was first arrested in July 2023 and charged with first-degree murder for the deaths of Melissa Barthelemy in 2009, Megan Waterman in 2010 and Amber Costello in 2010, all of whom were sex workers in their 20s.

Then, in January of this year, Heuermann was also charged with second-degree murder in connection with the death of Maureen Brainard-Barnes, a 25-year-old escort who disappeared in 2007.

All of these victims' remains were found over a decade ago, bound in a deserted spot on the north side of Long Island’s Ocean Parkway, near Gilgo Beach.

Investigators previously said they seized hundreds of electronic devices from Heuermann's home. They also discovered a "planning document" on a hard drive found in his basement used to "methodically blueprint" his killings, according to prosecutors. In a court filing Tuesday, prosecutors said that the so-called blueprint included details that matched Mack's death.

Authorities said that in recent searches of Heuermann's house and office, they found old newspaper clippings with articles about the Gilgo Beach killings that prosecutors believe he kept as "souvenirs."