MORE BONES FOUND IN LONG ISLAND SERIAL KILLER CASE-KILLER MAY KNOW POLICE TACTICS!

TOBAY BEACH, LONG ISLAND (PIX 11)— 

Now that they've found eight bodies hidden in roadside scrub in Suffolk County, police have expanded their search to neighboring Nassau County, where police say they have found more bones and a bag of clothes Monday. New information also suggests that the killer has extensive knowledge of law enforcement techniques.

At 10:30 a.m., Nassau County police stated in a press conference that more bones were found and they have requested an anthropologist to confirm if the bones are human. Investigators also discovered a bag of clothing, which may be related to the serial killer case.

Over the course of four months, Suffolk County investigators found eight bodies in the brush on the side of Ocean Parkway, in Gilgo Beach and Oak Beach. Police are convinced that there are more more clues, evidence and, possibly, more bodies to discover, which is why they're extending their search just over the Nassau County - Suffolk County line.

Tobay Beach is the staging area for cadaver dog and mounted units, fire department ladder trucks, a helicopter and dozens of crime scene investigators on foot. All of them search for inch-by-inch in scrub so thick that officers overhead in the helicopter often can only monitor ground crews' activity by radio -- they can't see their own fellow investigators through the brush.

All of these developments take place while new information surfaces about the suspected serial killer. It strongly appears that he -- and information so far indicates that it is a man -- is well versed in law enforcement tactics and investigations.

Four of the eight victims were recovered in searches in January of this year. One of them, Melissa Barthelemy, 24, of the Bronx, had a cellphone that a man used to call Barthelemy's teenage sister in the days after Barthelemy went missing on July 12, 2009. In all six calls, the man called from very public places like Times Square andMadison Square Garden, where thousands of people are on cellphones at any given time, making it virtually impossible for police to precisely locate the phone, and even if investigators could pinpoint the phone's location, they could not spot its user in the midst of so many people. In addition to that, the man kept his calls shorter than three minutes, the general length of time it would take to acquire additional identification information about the caller.

The identified victims were all prostitutes who made contacts through Craigslist. In each of their cases, the man who met them for the final time arranged their meetings through disposable cellphones, which a user can easily reserve using a false name. Police have identified the first four victims recovered as Ms. Barthelemy, Maureen Brainard-Barnes, 25, of Norwich, Connecticut, Megan Waterman, 22, of Scarborough, Maine and Amber Lynn Costello, 27, of North Babylon, Long Island.

The suspect's evasion tactics have some investigators concluding that the killer has sophisticated knowledge of law enforcement procedures, and may just possibly be in law enforcement himself.

The four sets of remains that have not yet been formally identified were all recovered since March 29th. Investigators say that those four victims are not necessarily prostitutes, like the four who have been identified.

Meanwhile, Jersey City sex worker Shannan Gilbert, whose disappearance late last year near the site of what is now the recovery operation sparked the entire investigation in the first place has yet to be found. Even though investigators have not released the identities of the remains that were most recently discovered, they have said that they are not those of Shannan Gilbert.