It was six years ago, when a Suffolk County police officer and his dog came across the remains of 24-year-old Melissa Barthelemy. Over the next several days, police discovered the bodies of three other young women, all wrapped in burlap and placed within about 500 feet of one another, buried in the marsh on Gilgo Beach in Long Island, New York. The remains were later identified as Amber Costello, Megan Waterman and Maureen Brainard-Barnes. All four women had worked as online escorts and had been missing for months or years.
On that December day in 2010, police had been searching for 24-year-old Craigslist escort Shannan Gilbert, who was last seen fleeing the home of a client she met on Craigslist in nearby Oak Beach on May 1, 2010.
Instead, what police discovered was a grisly graveyard. Over the next four months, six more sets of remains, including those of a toddler and an Asian male, were found, suggesting it might be a dumping ground for a serial killer or killers.
To this day, the Long Island Serial Killer case still remains a mystery but Suffolk County detectives still hold out hope that the biggest case in the department’s history will one day be solved.
“I am still confident we are going to solve it,” Suffolk County Police Chief Stuart Cameron tells PEOPLE. “We continue to make progress and I am very confident one day I will be talking about how the homicide unit solved the case.”
Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter.
Cameron says the detectives are making “steady progress” but serial killer cases aren’t easy to solve.
“Detective work is a slow and arduous process and it takes time especially with a complex case like this,” he says. “Some homicides are much easier to solve than others. When you have a serial killer case it is far more difficult in general to solve. In many cases they can take years. We have never given up on this case. We have never backed off working on it. It is hard to believe it was six years ago already. ”
While the foursome are likely linked, the connections between the other victims are more tenuous. The killer’s or killers’ handiwork was different. The victims weren’t all killed the same way, and they don’t all match the same demographic profile.
Cameron says detectives are keeping an open mind about the cases. “Right now we are open to anything,” he says. “It really depends on where the evidence takes us. To say we think it is one killer, two killers, three killers… I think we are basically open to whatever the evidence shows us to be.”
There are still leads to be investigated, says Cameron. “People do call us with tips still.”
Though it was the search for Shannan’s body that led to the others, Cameron says he doesn’t believe her case is linked and suspects she got lost in the inhospitable marshland.
With no sign of an arrest in sight, in December 2015, Suffolk County Police Commissioner Tim Sini pulled the FBI into the investigation, and in February, he launched a Gilgo Beach task force, assigning two full-time detectives from Suffolk County to focus only on the deaths, working side by side with an FBI agent.
“The FBI is experienced with serial killer cases across the country,” says Cameron. They have embedded expertise with serial killers that a local department like us just doesn’t possess. To me it just made perfect sense to be partners with them and get whatever assistance we can from them. ”
The FBI, says Cameron, is at the forefront of new technology and advancements in DNA so “if something new comes along we might be able to avail ourselves of it,” he says. “It is another benefit to staying in contact with the FBI on a regular basis.”
Solving the case is going to be difficult says former FBI profiler Mary Ellen O’Toole because the killer or killers has no intention of getting caught. “He puts a lot of effort into this thing,” O’Toole tells PEOPLE. “With a lot of serial murder cases they make sure police don’t have enough evidence so they don’t get apprehended. They are people who can fly under the radar because when they aren’t out there murdering someone they are living a normal life. ”
Like his serial killer brethren, the Long Island Serial killer has impulsivity issues, says O’Toole. “With this person, while impulsive, there is a maturity and patience here. He waits and reconnects with them. It is the excitement about playing with the victims. He is spending time with them but knowing once he meets her it could end in murder.”
In at least four of these cases, the killer contacted his victims through online ads as well as via cellphone before they vanished and the women had no idea they were pawns in his deadly game.
Brainard-Barnes, 25, disappeared first — in July 2007, from New York City — after checking out from a Super 8 motel. Friends suspect “I was the last person to see her alive,” her friend Sara Karnes told PEOPLE.
Barthelemy was last seen walking away from her Bronx apartment in 2009. Barthelemy’s mother, Lynn, told PEOPLE that she had no idea her daughter worked as an escort. “When she first went to New York City, she said she was working at a hair salon and then she said it got slow so she was bartending at some nightclub, but she was still working at the hair salon. That is about all I knew.”
Waterman disappeared from a Holiday Inn Express room she was sharing with her boyfriend Akeem Cruz in Hauppauge, New York, after she placed an ad on Craigslist on June 5, 2010. A video camera showed the 22-year-old Maine escort leaving the hotel around 1:30 a.m.
Amber Costello negotiated a $1,500 date with her alleged killer before she walked out of her Long Island home on September 2, 2010. The “She talked to the guy a couple of times, and she made a bad judgment call and it bit her in the a– in the end,” Costello’s sister, Kim Overstreet, told PEOPLE. “It was somebody she didn’t know.”
In March 2011, two months after police identified the first set of four remains, the remains of six more bodies were unearthed along the beach.
Four of the remains found were women, one was a female toddler and one was an Asian male wearing women’s clothing. Two sets of the remains were later linked to the dismembered torsos of two women discovered in Manorville, about 40 miles away. One of them was identified as 20-year-old prostitute Jessica Taylor whose torso was found in Manorville in 2003. The rest of the remains have never been identified.
Cameron says he is very aware of the criticism leveled against the department by families who don’t believe they want to solve the case because some of the women were escorts but he says it is unfair.
“It is very high priority for the police department to solve this,” he says. “People should not think we are not doing everything we can to bring this person to justice.”