With all four bodies now identified, Suffolk officials said definitively Monday they believe the women discovered in Gilgo Beach last month were the victims of a serial killer.
There were striking similarities among the victims.
All were white, in their 20s and working as prostitutes. All went missing after meeting clients they found on Craigslist or other Internet sites. The way they were killed was "substantially similar," said Suffolk District Attorney Thomas Spota, but police did not describe the means.
Neither would describe what other progress has been made in finding the women's killer, but they appealed for outside help - particularly from people involved in the prostitution trade.
"I find it very hard to believe that people engaged in the same business as them [don't] know something," Spota said.
Police working with cadaver-sniffing dogs found the skeletons on Dec. 11 and 13, all wrapped in burlap and left unburied off an isolated, barrier-island road within a quarter-mile of each other. All were positively identified through a DNA match with family members.
One of the newly identified victims, Maureen Brainard-Barnes, 25, of Norwich, Conn., was last seen alive in Manhattan on July 9, 2007, police said. Police believe the killer left her body in Gilgo Beach shortly after that.
Another victim, Melissa Barthelemy, 24, went missing from her Bronx apartment nearly two years to the day later, on July 12, 2009.
City investigators listed Barthelemy as an involuntary missing person after her every-other-day call to her family abruptly ended, raising alarm, the law enforcement source said.
Shortly afterward, her sister received a call from a man using Barthelemy's cell phone, referring to her as a "whore," according to the source.
Costello was never reported missing, police confirmed yesterday.
David Van Norman, an expert on identifying missing persons and the deputy coroner investigator with the San Bernardino County Sheriff-Coroner's Department in California, said missing women working as prostitutes are much more likely to go unreported than others. If they are found dead, their remains are also likely to go unidentified for longer periods of time.
Spota said sex workers should be on "very high alert" as the search for a suspect or suspects continues. Craigslist officials have cooperated in the investigation, he said.
Advocates for sex workers in New York Monday said they would put out alerts about the developments in the Gilgo Beach case.
"Sex workers are vulnerable to violence every day," said Sienna Baskin, co-director of the Sex Workers Project of the nonprofit Urban Justice Center.
The first body found on Gilgo, now known to be Barthelemy, was discovered during a search for the possible remains of another missing women who worked as a prostitute, Shannan Gilbert, 24, of Jersey City.
The discovery triggered a massive search of the barrier island that turned up three more skeletons. Gilbert proved not to be among them; she remains missing and her fate is unknown.
Police said they do not believe more bodies are in the area.
Waterman's mother, Lorraine Ela, said Monday she did not recognize the names of the other women.
"I'm very glad they were able to identify the other women so now maybe their families can put them to rest, like we are with Megan," she said.
The DNA matches were made in a New York City forensics lab and confirmed by the Suffolk medical examiner's office on Friday. All the remains have been returned to Suffolk.
Waterman's cremated remains will be returned to Maine Wednesday before a planned Sunday memorial service, Ela said.
With Anthony M. DeStefano