Wife, 2 Children of Long Island Serial Killer Suspect Rex Heuermann Were Out of State When Women Were Killed

New York authorities said the the family of Long Island Serial Killer suspect Rex Heuermann was out of state at the time of the three murders he is accused of.

At a press conference Friday, authorities said Heuermann, who has been charged with three counts of first degree murder and three counts of second degree murder in connection with the deaths of Amber Costello, Melissa Barthelemy and Megan Waterman, was allegedly linked to the killings by cellular data from his burner phones, his car and hairs reportedly found at the crime scene.

"Rex Heuermann is a demon that walks among us," Suffolk County Police Commission Rodney Harrison claimed at the press conference. "A predator that ruined families. If not for the members of this task force he would still be on the streets today. Even with the arrest, we are still not done."

According to Suffolk County District Attorney Ray Tierney, investigators focused on Heuermann after a witness who knew Costello connected a Chevrolet Avalanche owned by Heuermann to the case.

Authorities alleged Heuermann communicated with his victims using burner phones and would dispose of the phones shortly after their deaths.

Authorities also said that they discovered that Heuermann allegedly paid close attention to the case and searched on the Internet about how the investigation was going.

He was also allegedly "compulsively" searching for information about the victims and their relatives. “Their sisters, their children and he was trying to locate the individuals,” Tierney

They also allegedly found images of women being abused and raped on his devices, authorities said.

Police said the initial tip about the Chevrolet Avalanche led to a "comprehensive investigation of [Heuermann] which consisted of over 300 subpoenas, search warrants and other legal processes to obtain evidence," according to the criminal complaint against him.

Police also found cellphone billing records that corresponded with cell site locations for burner phones used to arrange meetings with the victims, the complaint alleges.

Heuremann, police said, also lived in Massapequa Park — the town where the victims allegedly disappeared from.

The Gilgo Beach case, dubbed the “Long Island Serial Killer” case, traces back to the discovery of multiple bodies starting in December 2010. Authorities eventually unearthed 10 sets of remains in the area and have said they believe at least four of the deaths — all of women — are linked, raising the specter of one or more serial killers using the area as a dumping ground.

Investigators first came upon the bodies of four sex workers in the marsh at Gilgo Beach. The remains were later identified as belonging to Costello, Barthelemy, Waterman and Maureen Brainard-Barnes. (Heuermann has not been charged in connection with Brainard-Barnes' death.)

All four women had worked as online escorts and had been missing between 2007 and 2010.

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Brainard-Barnes, 25, disappeared first — in July 2007, from New York City — after checking out from a Super 8 motel.

Barthelemy, 24, was last seen walking away from her Bronx apartment in 2009.

Waterman disappeared from a Holiday Inn Express room she was sharing with her boyfriend Akeem Cruz in Hauppauge after she placed an ad on Craigslist on June 5, 2010.

Costello negotiated a $1,500 date with her alleged killer before she walked out of her Long Island home on Sept. 2, 2010.

Initially, authorities had been looking for Shannan Gilbert — another sex worker who escaped from a home and called 911. After police made the discoveries of the initial four bodies, they uncovered more human remains near beaches in Nassau and Suffolk Counties — including those of Gilbert.