Even as skeletal remains of more murder victims are dug out from a marshy Long Island beach, the police investigation has focused on the possibility of three serial killers having dumped dead bodies in the same area.

As many as ten sets of dead bodies have been found out from the New York area beach ever since police started to scan the area as part of its search for a Craigslist prostitute who went missing last year. Though ten bodies have been dug out from the area, the woman, Shannan Gilbert, has not been found yet.

Police are investigating if the remains of a skull and torso discovered on Monday belong to one of the victims of the notorious serial killer Joel Rifkin. Rifkin had admitted in 1993 that he had dismembered and dumped the bodies of some of his victims in the Long Island area. Bodies of three of his 17 victims had never been found.

These [bones] are so old that roots were growing around the vertebrae and the skull ... These could be one or two of Joel Rifkin's victims who were never found, or the work of another killer, an investigator told New York Post.

The latest discovery of two bodies, which belonged to a man and a child, have given clues to the police about the possibility of a serial killer other than the Craigslist killer having used the area for dumping dead bodies.

Significant differences in the way in which the bodies were disposed, as well as DNA evidence have forced the police to consider the possibility of more than one serial killer involved in the murders, though they are not ruling out the one-killer theory.

POLICE OUTLINE OF THE KILLER

According to the Daily Mail, the police suspect the killer is a man, who has considerable knowledge of police investigation, is tech-savvy, and one with intimate knowledge of the area. He is an intelligent person who could be living a normal life.

The report points out that the killer could be the one who made taunting phone calls to the sister of one of the dead women. He made short telephone calls from a telephone box in a crowded area, suggesting that he knew how authorities try to locate a person by tracing phone calls.

He is a guy aware of how we utilise technology. Frankly, people are thinking maybe he could be a cop - either one still in law enforcement or one who has moved on ... Without question this guy is smart, this guy is not a dope. it's a guy who thinks about things, an officer told the New York Times.