Updated July 14, 2023 at 5:15 PM ET

As recent as last month, the alleged Gilgo Beach serial killer searched for updates in the investigation. According to court documents, he impulsively searched for pictures of the victims and their relatives, as well as answers to questions like "why hasn't the long island serial killer been caught."

On Friday, that man, Rex Heuermann, was charged with the murders of three women — Amber Lynn Costello, Megan Waterman and Melissa Barthelemy — whose remains were found near Gilgo Beach on Long Island over a decade ago. He is also the prime suspect in the killing of Maureen Brainard-Barnes, according to court records.

In total, they make up four out of the 11 bodies found near Ocean Parkway between Nassau and Suffolk counties.

"Even with this arrest, we're not done. There is more work to do in this investigation regarding the other victims of the Gilgo Beach bodies that were discovered," Suffolk County Police Commissioner Rodney Harrison said at a news conference late Friday afternoon.

Heuermann of Massapequa Park was a long-time successful architect with an office in Midtown Manhattan. His arrest is considered a breakthrough in a decade-long investigation that made national headlines and inspired the 2020 Netflix film Lost Girls.

The victims

Between 2010 and 2011, police uncovered a series of remains that belonged to 11 people but the killings likely began as early as 1996, according to Suffolk County Police.

The dead also included Jessica Taylor, Valerie Mack and Shannan Gilbert. All seven women were believed to be in their 20s, police said.

The identities of remains belonging to four others — a female toddler, the toddler's mother, an Asian man and one women whose remains were partly also found on Fire Island — are still unknown.

All of the victims were discovered near Ocean Parkway between Nassau and Suffolk counties — six were less than a mile apart from each other.

The suspect

Several pieces of evidences tied Heuermann to several victims, according to court documents released on Friday.

For starters, Heuermann lived in Massapequa Park, where a few of the victims were last seen.

One witness also described seeing a victim, Costello, driven by a man in a Chevrolet Avalanche. Later, it was discovered that a Chevrolet Avalanche belonged to Heuermann.

Subpoenas and search warrants later linked Heuermann to multiple burner cellphones used to contact three victims. An email associated with Heuermann's suspected burner cellphones was repeatedly used to conduct "thousands of searches" related to "sex workers, sadistic, torture-related pornography and child pornography," court records said.

There were also over 200 searches for pictures of several victims and their relatives, as well as updates the police investigation.

Dispute over Shannan Gilbert's death

Although Gilbert's disappearance led to the discovery of the serial killings, Suffolk County Police has called her death unrelated to the murders.

The remains of Gilbert were uncovered in Oak Beach near Ocean Parkway, about three miles east of where many of the other victims were found.

According to a 911 call made by Gilbert in May 2010, Gilbert appeared to be in an argument with two men, a client and her driver, in Oak Beach. At one point, she told dispatchers that she was lost and believed her life was in danger. Moments later, Gilbert ran off, according to Suffolk County Police.

Her personal items and later, her remains, were found in a nearby marshland, which officials described as impossible to navigate.

"These reeds can grow over 12 feet tall. They can disorient someone inside them, causing them to lose a sense of direction," Detective Lt. Kevin Beyrer, with the Suffolk County Police, said in 2022.

The cause of Gilbert's death was ultimately ruled as undetermined due to insufficient evidence, but Beyrer has called it "most likely an accident."

Sherre Gilbert, her sister, has firmly refuted that claim. She told ABC 7 last year that it's difficult to imagine that her loved one would get rid of her clothes and phone and run wild into the marsh.

Gilbert's family has demanded for another investigation to be done, this time by the state attorney general rather the local police.

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