YAPHANK, N.Y. — One of four women found dumped along a deserted stretch of Long Island beach highway last month has been identified as that of a missing Craigslist escort from Maine, and New York authorities said Wednesday they were close to identifying the other three bodies.

“Progress is being made,” Suffolk County District Attorney Thomas Spota said of the mystery that began to unfold Dec. 11 when police found the first of the bodies just steps from Ocean Parkway, a narrow strip of highway that leads to Jones Beach State Park.

The other three bodies, including that of the missing Maine woman, were found two days later during a follow-up investigation. Authorities said Wednesday that the New York City medical examiner’s office, which is assisting in the probe, identified the remains as that of Megan Waterman, a 22-year-old from Scarborough, Maine.

She last was seen at a Holiday Inn Express in Hauppauge, N.Y., on June 6.

Scarborough Police Chief Robert Moulton said detectives from New York were in Maine on Wednesday to meet with his detective, as well as Waterman’s mother and grandmother. Moulton said it’s a “sad day,” but the revelation also brings some closure for the family.

“Obviously, you hold out hope in these matters, but we’ve had a sense for a period of time now that this wasn’t going to end well,” Moulton said.

Lorraine Ela, the woman’s mother, said police confirmed her daughter was among the dead. “They said the DNA was a match and there was an investigation going on.” She said police weren’t able to tell her anything more.

Waterman went missing after traveling to New York last Memorial Day weekend with Akeem Cruz, a 21-year-old Brooklyn man described as her boyfriend. Cruz is now serving a 20-month sentence at the Maine Correctional Center for drug trafficking.

Ela told The Associated Press that Waterman always called three times a day to speak to her 4-year-old daughter, Liliana, but the last call came on the night of June 5. When police searched the hotel room they found Waterman’s clothing, makeup, cell phone and other belongings, Ela said. Family members said Waterman was aware of the potential dangers of advertising her services online, but was an adult and could make her own choices.

Police actually were looking for another missing Craigslist escort when they happened upon the bodies near the beach. They since have said the missing woman, from New Jersey, was not among the dead.

The four bodies were found strewn over a quarter-mile stretch of marshy grasslands, overgrown shrubbery and sea grass on the barrier island. Spota predicted the other bodies would be identified in a “very short period of time.”

He said since the bodies were found, relatives of other missing women have contacted authorities and tests are under way to compare DNA samples, as well as medical and dental records with the beach victims. He would not comment on whether police had identified any suspects in the killings.

Although Police Commissioner Richard Dormer had initially said a serial killer may be responsible, authorities since have backed away from that assertion, saying all possibilities were being investigated.

Neither Spota nor Dormer would comment Wednesday on statements made last month by police that the victims likely were killed elsewhere and dumped along the parkway. The highway sits on a narrow strip of land that divides the Great South Bay from the Atlantic Ocean. A four-lane parkway runs through the middle, connecting Jones Beach State Park with several state- and town-run beaches to its east.

Associated Press writer Clarke Canfield in Portland, Maine, contributed to this report.