Her Disappearance Led Authorities to the Gilgo Beach Serial Killer. So Why Isn’t Shannan Gilbert's Death Considered a Murder?

Shannan Gilbert disappeared in 2010, and the last record of her is a chilling 911 call she placed on the night she vanished

<p>Jersey City Police</p> Shannan Gilbert

Jersey City Police

Shannan Gilbert

Shannan Gilbert disappeared on May 1, 2010, after visiting a client she met on Craigslist, in the gated community of Oak Beach on Long Island, N.Y.

The night she vanished, she made a haunting call to 911.

"There's somebody after me," she told an operator before fleeing from the client’s home at around 5 a.m.. "Somebody's after me — please."

Gilbert, 23, ran to an elderly neighbor’s house, knocked on the door and asked for help before tumbling down the stairs and darting off. The elderly neighbor called 911, as did another neighbor, who told police she was afraid to let Gilbert into her home.

But when police finally dispatched officers, Gilbert was nowhere to be found.

Her disappearance prompted a search, which led to the discovery of four bodies — Melissa Barthelemy, Amber Costello, Megan Waterman and Maureen Brainard-Barnes — in December 2010. All four women, like Gilbert, worked as online escorts and went missing between 2007 and 2010. (Additional searches turned up the skeletal remains of seven more people, including a toddler.)

<p>Suffolk County Police Department; Barthelemy family; Suffolk County Police Department (2)</p> Maureen Brainard-Barnes; Melissa Barthelemy; Megan Waterman; Amber Lynn Costello

Suffolk County Police Department; Barthelemy family; Suffolk County Police Department (2)

Maureen Brainard-Barnes; Melissa Barthelemy; Megan Waterman; Amber Lynn Costello

The search for the suspected Gilgo Beach Serial Killer went unresolved for more than a decade until July 2023 when authorities allegedly linked 60-year-old architect and father of two Rex Heuermann via DNA evidence and phone calls to the murders of Barthelemy, Costello, Waterman and Brainard-Barnes. He has since been charged in connection with their deaths.

On June 6 of this year, Heuermann was charged with two additional counts of murder in connection with the deaths of Sandra Costilla in 1993 and Jessica Taylor in 2003.

“Shannan will be remembered for the girl who by her death exposed the truth and the killer,” Gilbert family attorney John Ray tells PEOPLE. “What Shannan's case did is it forced the authorities to finally pursue the evidence that existed for the other girls. Shannan kept the pressure on all those years, even though she was dead.”

Related: Police Say Accused Long Island Serial Killer Rex Heuermann Allegedly Kept Track of His Victims' Families

<p>AP Photo/Seth Wenig</p> Mari Gilbert

AP Photo/Seth Wenig

Mari Gilbert

What happened to Shannan Gilbert

A year after the remains of Barthelemy, Costello, Waterman and Brainard-Barnes were found, Gilbert’s skeletal remains were discovered hidden deep in the overgrown Gilgo Beach brush on December 13, 2011, near the Oak Beach gated community where she was last seen.

Gilbert’s mother Mari became a vocal critic of law enforcement’s handling of her daughter’s case, insisting Shannan’s death was a homicide. (Tragically, Mari was fatally stabbed more than 100 times by her other daughter, Sarra, in July 2016.)

As part of her advocacy, Mari enlisted famed forensic pathologist Michael Baden to perform an autopsy on Shannan’s remains.

Related: Rex Heuermann's Estranged Wife Says Suspected Serial Killer 'Is Not Capable' of Murder: Lawyer

Baden concluded that Gilbert's death was consistent with homicidal strangulation, opining that damage to a small bone in Gilbert's throat possibly indicated that it was fractured when she was murdered.

<p>Suffolk County Sheriff's Office</p> Rex Heuermann

Suffolk County Sheriff's Office

Rex Heuermann

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Mari, prior to her death, also fought for access to the 21-minute tape of Gilbert's 911 call. In 2022, police released the chilling tape in which Gilbert said "somebody's after me."

Still, the details of how she vanished remain murky. Police have long suspected that Gilbert somehow got lost in the inhospitable marshland and died accidentally — either of exposure or accidental drowning.

Related: Where Is Rex Heuermann Now? All About the Suspected Long Island Serial Killer, Accused of Murdering at Least 4 Women (Exclusive)

At a 2022 press conference, then-Police Commissioner Rodney Harrison said the FBI's behavioral science unit evaluated Gilbert’s case as well as the 911 call.

"Based on the evidence, the facts, and the totality of the circumstances, the prevailing opinion in Shannan's death, while tragic, was not murder and was most likely not criminal," Harrison, who resigned in late December of 2023, said.

Today, the Suffolk County Police Department still maintains Gilbert’s death was “an unfortunate accident” but “the department will continue to evaluate any information that the public may have to help determine a definitive cause of death in [Gilbert’s] case,” according to the department’s gilgonews.com website, which has since been taken down.

Ray says he still believes that Gilbert was murdered and will continue to seek answers about what happened to her. “It's not over,” he says. “We're going to keep the pressure on the police and district attorney, as much as we can.”

Anyone with information about Shannan Gilbert is asked to contact Crime Stoppers at 1-800-220-TIPS.

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