Gilgo Beach murders suspect Rex Heuermann continued to engage in “disturbing” activity in the months leading up to his July arrest, police say.

“He’s somebody that was still engaging in activity that was disturbing, be it his internet searches, be it engaging in other activities that he shouldn’t be engaging in,” Suffolk County Police Commissioner Rodney Harrison said, according to Newsday. “That’s something I was very, very passionate about, regarding, ‘We need to see what his lifestyle is.”

Harrison also noted that he “can’t talk about if [Heuermann] was preparing to kill again.”

Heuermann, 59, was arrested July 13 at his Massapequa, Long Island home and charged with the murders of three sex workers: Megan Waterman, Melissa Barthelemy and Amber Lynn Costello, whose remains were discovered near Gilgo Beach in 2010. The father of two is also the main suspect in the killing of Maureen Brainard-Barnes.

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The investigation took a turn when investigators, who had been keeping tabs on Heuermann for months, obtained the New York City architect’s DNA from discarded pizza crust, which matched DNA found on the burlap that was used to wrap the victims, prosecutors have said.

Suffolk County District Attorney Ray Tierney said that a “massive amount” of material has been collected over the span of the investigation, after handing over eight terabytes-worth of evidence against Heuermann in court earlier this month.

Harrison is optimistic about the strength of the case against the Long Island native, according to Newsday. The police commissioner also defended his previous comments about Heuermann, in which he called him a “demon that walks among us, a predator that ruined families” during a press conference after the arrest.

“I’m very confident that Mr. Heuermann’s our subject,” Harrison told the news outlet Wednesday. “Because of my confidence, I’m gonna call him what I wanna call him — somebody that ruined families, somebody who’s a predator, somebody who shattered lives. And not just one, several, and there may be more. I didn’t say that there is, but there may be more. If the family members have a problem with me calling him a demon, then I’ll apologize.”

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Heuermann pleaded not guilty last month to multiple charges of first- and second- degree murder relating to the 13-year-old “Gilgo Four” case.

In total, the bodies of 11 people were found across two Long Island counties in 2010 and 2011.

“We were able to bring comfort to three families, we’re very close to a fourth one, but we still have more work to do to identify the subject or subjects that were involved with the other bodies that were discovered,” Harrison told Newsday.

Last week, the Suffolk County District Attorney’s Office identified Jane Doe No. 7, found near the bodies of the Gilgo Four, as 34-year-old Karen Vergata.

Tierney shared in a press conference that Vergata was working as an escort in midtown Manhattan when she disappeared around February 14, 1996. At the time, no one reported her missing.

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The investigation into Vergata’s death is ongoing, however, Tierney noted that Heuermann has not been charged in connection to her death or that of any of the other bodies found other than Waterman, Barthelemy and Costello.

When asked if Long Island residents should be concerned that a serial killer is still at large in relation to the other bodies, Harrison said: “I wish I could give you an answer. I can’t tell you at this time. Is Rex Heuermann going to be held accountable for the other bodies on Ocean Parkway? Time will tell.”