Authorities reportedly are considering that a former cop or someone familiar with law enforcement procedure is behind the killings of four online escorts whose bodies were found on a remote New York beach.
Police say evidence suggests that whoever dumped the women -- all in their 20s and found wrapped in burlap bags -- is knowledgeable of police investigative tactics and familiar with the area of Long Island where the bodies were found, according to multiple press reports.
Authorities have found a total of eight bodies in thick brush along a remote stretch of parkway between Ocean Beach and Gilgo Beach. The New York Post reports that investigators found a ninth set of remains Monday but Nassau County Police would not confirm that the bones discovered at New York's Jones Beach State Park are human.
A spokeswoman with the Suffolk County Police Department told FoxNews.com that police have not determined whether the four additional bodies found in the last two weeks are linked to the women found in December.
The most recent remains, found several miles away from the escorts, included the body of an infant or child, the New York Post reports, leading police to consider that the bodies were victims of multiple killers.
Police expanded their search for more possible victims into Nassau County on Monday. About 125 searchers, some with dogs and others on horseback, scoured Jones Beach State Park for more possible victims.
Investigators are also exploring possible links to the suspected serial killer who murdered prostitutes in New Jersey, officials have said.
The New York Post and the New York Times, citing unnamed sources, have reported that the killer may be a former cop or someone familiar with law enforcement procedure.
The person believed to be the killer had reportedly made taunting phone calls to the teen sister of victim Melissa Barthelemy shortly after she disappeared in July 2009. The calls were difficult for police to investigate because they were all under three minutes and made from crowded places, like Madison Square Garden and Times Square.
An official with the Suffolk County Police Department would not confirm to FoxNews.com that authorities are eyeing an ex-cop in the investigation.
"We haven’t said if we think it’s someone in law enforcement," the official said.
Criminal profilers say serial killers are often social and would appear to have a normal life with family and friends as opposed to being a loner.
The disappearance of 24-year-old N.J. resident and Craigslist escort Shannan Gilbert led investigators to the Suffolk County beach spot late last year where they found four skeletal bodies of female prostitutes. Four more bodies that have yet to be identified were found when officers returned to the area in the past two weeks, but all eight were found within a three-mile radius on the north side of the parkway.
None of the found victims, however, is Gilbert, whose case remains open.
A Suffolk County investigator who declined to be identified because of the ongoing case told The Associated Press that detectives are taking a methodical approach to finding the suspect, poring over credit card records of the victims to track their movements and where they spent their money in the area, MyFoxNY.com reports.
Cell phone calls made by the women are also being tracked, and computer records of their communications and appointment records have also been viewed.
"These kinds of investigations have to take slow steps; you don't want to jump to conclusions," Katherine Ramsland, a professor of forensic psychology at DeSales University in Center Valley, Pa., and author of "The Human Predator: A Historical Chronicle of Serial Murder and Forensic Investigation," told MyFoxNY.
"They are looking at the evidence to determine what may be similar about the victims, but they also want to look at dissimilarities," she said.
FoxNews.com's Cristina Corbin and the Associated Press contributed to this report