In December 2015, the FBI joined the investigation.

Why did that collaboration not happen for so many years?

"It didn't happen because of politics. We had a police chief in Suffolk County, as well as a DA, that did not seem open to FBI involvement," recalled Kristin Thorne.

On Jan. 16, 2020, police released photos of a belt imprinted with the letters "H-M" or "M-H" to the public. Police say they believe the belt was handled by the suspect.

Two years later, Suffolk County Police Commissioner Rodney Harrison announced a new task force to investigate the Gilgo Beach murders.

The next episode of "Eyewitness to Gilgo Beach" drops Thursday, Feb. 29. Never miss an episode - hit follow for all future installments of our series.

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After a year and a half of searching, investigators found the skeletal remains of Shannan Gilbert on Gilgo Beach.

"What was the ultimate stunner in all of this is that they believed -- and still do believe -- that Shannan Gilbert was not murdered. That Shannan Gilbert died in an accidental drowning," recalled reporter Josh Einiger.

A few years later, Shannan Gilbert's mother, Mari Gilbert, who is credited for the discovery of the Gilgo bodies because of how she pushed for her daughter's search, is found stabbed to death in her apartment.

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Investigators had found 10 bodies and identified five of them, but they were still searching for Shannan Gilbert.

"This investigation started because Shannan Gilbert disappeared," said reporter Kristin Thorne. "It wasn't until Shannan Gilbert disappeared that her family started to hold police accountable and say -- you have to get out there and try to find Shannan Gilbert."

Investigators found a cell phone, lip gloss, shoes, and a pocketbook they say belonged to Shannan Gilbert on Gilgo Beach.

Yet they did not believe her death was related to the 10 bodies they found in the area.

Why?

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Investigators continued to find more bodies, but the remains differed from those of the "Gilgo Four".

Police found three more victims in the area between Oak Beach and Gilgo Beach, bringing the total count of victims to eight.

Investigators identified the victims as Jane Doe Number 6, a baby girl and an Asian man.

Investigators then say they believe they are looking for three, if not four, killers.

"This is around the time that it got complicated to tell this story," reporter Josh Einiger recalled.

We shed light on this complex stage of the story.

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Shannan Gilbert's disappearance in 2010 sparked the discovery of 11 bodies on and near Gilgo Beach on Long Island.

"One of the most significant things I've ever heard at any kind of public official say, I think it was the first full day after that first report that we did," recalled Einiger. "There was a press conference with the man who was then the police commissioner. And he said something that to this day, I remember everything about what he said and how he said it."

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It began on a regular garden variety day in December, when Eyewitness News reporter Josh Einiger and his photographer, Tony Saturno, were covering stories in Suffolk County.

"We were on our way back and we got a call from the desk - saying 'there's a crime scene, there's a maybe body discovered', way down south on Ocean Parkway. Go check it out," Einiger said.

When they arrived at the scene, it was cold and pitch black. There were four crime scenes along the beach and spotlights set up.

"It was clear at that point that it was something," recalled Einiger.

Nobody quite understood it was something that we'd be talking about over a decade later.

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The news coverage of the Gilgo Beach murders began with a single live shot: a live remote, plagued with technical difficulties, from a barren and frozen beach off Long Island's South Shore. Little did anyone know how important that report would be. No one could have predicted the international spectacle that would follow. That first report was on an impossibly cold December night in 2011. They had found bodies on a remote Long Island beach. And soon, more bones turned up in the sand. It was a serial killer's graveyard by the sea. The story of the Gilgo Beach murders - and the hunt for the suspect - is as convoluted as it is creepy, and Eyewitness News tells it like nobody else. From the first gruesome discoveries to an arrest more than 12 years later, our team of reporters describes the twists and turns of covering a true crime mystery in real time. Follow "Eyewitness to Gilgo Beach" now and never miss a new episode of our true crime series.

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