Rex Heuermann was arrested Thursday and is now charged with three counts of first-degree murder.
[Ads /]
ALSO WATCH | Exclusive video of Rex Heuermann's arrest
Exclusive: Surveillance video of Gilgo Beach murder suspect's arrest
Back in January, federal investigators who were tailing Rex Heuermann recovered a pizza box he had thrown in the garbage in Midtown Manhattan.
A swab of his DNA from that pizza crust was tested and found to be a match with a hair that was discovered on one of the victims.
Heuermann, an architect who lives in Massapequa Park, is charged in the deaths of Melissa Barthelemy, Megan Waterman and Amber Costello.
While he is not charged in the death of Maureen Brainard-Barnes, the indictment said Heuermann is the "prime suspect in her death."
Investigators point out that all four cases shared a number of similarities, including that all of the women had contacted shortly before their disappearances with a person using a "burner" cell phone.
Cell phone data in particular played a big role in the probe.
[Ads /]
Investigators were able to use track the burner cell phones used to arrange meetings with three of the four victims as well as taunting calls made to Barthelemy's sister made from the woman's own cell phone.
Discarded pizza crust led investigators to Gilgo Beach suspect
Heuermann used one of his burner phones "to conduct thousands of searches related to sex workers, sadistic, torture-related pornography and child pornography, court records said.
Other searches were "related to active and known serial killers," and the disappearances of the Gilgo Beach victims:
"Why hasn't the Long Island serial killer been caught," one search said according to court records.
Heuermann also searched for and viewed articles about the police and FBI task force investigating him.
[Ads /]
One email account revealed a selfie Heuermann apparently took and "sent to other persons to solicit and arrange for sexual activity," court records said.
Cell calls were traced to areas -- called a "box" -- around his home on Long Island and office in Manhattan.
Heuermann was first eyed in the cases in March 2022. At the time, he was connected to a pickup truck a witness had seen where a victim disappeared in 2010.
Heuermann spoke his name and nothing else during his arraignment before Judge Richard Ambro Friday.
Court-appointed counsel Michael Brown entered a not guilty plea on Heuermann's behalf.
Judge Ambro ordered him held on no bail pending a bail application based on the "extreme depravity of the allegations," the judge said.
----------
* More Long Island news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
* Follow us on YouTube