Police on Long Island now believe a single serial killer may be responsible for the 10 bodies found along a deserted oceanside highway, shifting their theory away from multiple killers as they previously believed.

Police also don't believe the disappearance of Shannan Gilbert is connected to the killings.

Suffolk County Police Commissioner Richard Dormer told NBC New York Tuesday that police now think a single person is behind the deaths of the human remains found on Gilgo Beach, most of them in the last year.

Most were young women, but one body was a child and another was a man.

"The common denominators that we have now indicate that it's possibly one killer," Dormer said in a phone interview. "We've had the same dumping ground, sex workers, young women -- even though there were the Asian male and the toddler -- but we think they were connected to the sex trade in some way. And these common denominators indicate we have the one person committing these crimes."

Five of the bodies have been identified as working prostitutes. One woman's mother, Lorraine Ela, told NBC New York on Wednesday that she was not surprised by the single-killer theory, and had believed it herself since the beginning.

The mother of Megan Waterman said she feels like law enforcement has not had much compassion for the families of the women.

"I think the reason they don't have the compassion that they should have is all these girls were escorts," Ela said. "They're still human beings. It doesn't matter what they did for a profession -- they did not deserve to be murdered by somebody."

Newsday also reported that Dormer doesn't think the death of Gilbert, a sex worker who was seen frantically running from a house in Oak Beach early May 2010, is connected. Her body has not been found.

"We believe that it's just a coincidence that she went missing in Oak Beach and the bodies were found on Gilgo Beach, which is right across Ocean Parkway and farther west," he told Newsday. "The M.O. is completely different, the scenario is completely different."

But Dormer acknowledged the fear there will be new victims. "That's why we are moving as fast as we possibly can to apprehend this person," he told the paper.

In the interview with NBC New York, he added that another initial theory that the killer worked in law enforcement has been "debunked."

"It's not unusual for people to be very familiar with how police conduct investigations, and how criminals try to evade capture," Dormer said. "That came up early in the investigation, but it's not credible at this time."

Between December 2010 and April of this year, the remains of eight women, a male and a female toddler were found dumped along a stretch of Ocean Parkway. Five of the women were identified and found to have been working prostitutes.

Among the remains still unidentified are the toddler and a woman believed to be her mother, and the man, also believed to be a sex worker.

Initially, police said there could be as many as three killers behind the bodies, all using the brush along the parkway as a dumping ground.

But, Dormer told NBC New York Tuesday, police now believe one killer is behind the dumped bodies, though even "that could change" as the investigation moves forward.

Detectives also believe the killer is from Long Island.

"The person has got to be comfortable with the locations," Dormer said, citing the long distances between Manorville and Gilgo Beach, and from Davis Park to Gilgo Beach. "That's the theory, that it's a Long Islander."

"That's a huge distance, so somebody has to be familiar with the Long Island area and comfortable with that area," Dormer said.

Dormer said the case remains "high priority," and that police are "still actively investigating this."