April 11, 2011 -- The heavily thicketed ground that borders a highway along a stretch of New York beaches where as many as 10 bodies have been found is now being examined as the disposal site for a serial killer and a possible dumping ground for other killers.
More bones were found today along the Long Island beaches and have been sent to the medical examiner's office to determine whether they are from one or two people. One of the remains is just a skull.
Authorities involved in the painstaking probe along the popular stretch of public beach now involves more than 125 state, federal investigators and local investigators from two neighboring counties.
Investigators have said they believe that a serial killer was responsible for the murders, and Nassau County Executive Edward Mangano said today that police are looking for "the animal that has obviously taken the lives of a number of people."
But probers now says that they cannot rule out the likelihood that more than one killer will be linked to the bodies which total seven sets of adult human remains, a toddler's remains and the bones found today that may be from one or two people.
"Now the question is connectivity," one law enforcement supervisor told ABC News. "Geographically it is secluded and makes a perfect dumping ground."
According to authorities, any differences in the method of murder, disposal, burial, and any DNA evidence will be among the elements of a rigorous forensic examination. The probe will include the assistance of state police and FBI agents including evidence collection experts, behavior science investigators and profiling gurus.
According to ABC News sources the first bodies discovered, now badly decomposed, were wrapped in burlap and were prostitutes who advertised on Craigslist.
In addition to those grisly skeletal remains found buried in the thick ground cover beside the ocean, authorities continue to search for Shannan Gilbert, a 24 year old sex worker who also advertised on Craigslist and was last seen near the beach area shouting, "He is trying to kill me."
The second set of remains, discovered over the past two weeks, were not wrapped in burlap and one was a toddler. Authorities have not said whether the toddler's remains were linked to one of the adult remains, or is unrelated.
According to multiple sources familiar with the investigation a number of persons are under investigation in connection with the first eight corpses, and those include persons of interest with a law enforcement or emergency service background, and familiarity with the beach. All of those who were described to ABC News were local suspects. They were under examination for any role in the killing of some or all of the victims
The corpses were strewn along a several-mile stretch that includes state run and county beaches. The stretch begins about 45 minutes from Manhattan and includes the popular Jones Beach State Park.
"In some respects, the location and the usage of the internet to contact some of the victims offered the same features for the killer or killers: seclusion and anonymity," said Michael Balboni, former deputy Secretary for Public Safety for the state of New York.
One of the bodies found so far is that of prostitute Melissa Barthelemy. Barthelemy's teenage sister told "Good Morning America" today that she has received taunting phone calls from a man who is believed to have killed her sister.
"I just don't understand why he chose me...how many other girls and how many other families...why was I chosen, why was I taunted?" she told "GMA."
The teenager was shown in silhouette and spoke on the condition that she not be identified out of growing fears for her safety.
Her older sister disappeared in July 2009. Her body was found in December on Gilgo Beach in New York's Long Island area along with the bodies of three other women. All found women were prostitutes who advertised on Craigslist, police said.
Barthelemy's sister said she was just 15 when she received the first in a series of calls from the man believed to be the killer. The calls eerily came from her sister's cell phone. The man sounded calm, despite his angry words, the teenager said.
"They were very taunting and angry words," she said. "[It was] very scary. My heart would stop and I just didn't know what to do. I'm scared of my own protection, the fact that he's calling my phone... I have to be worried about is that going to happen to me one day?"
She said that it was frustrating because the man would allow her to ask few questions about her missing sister's whereabouts.
"It was very frustrating, it broke my heart.... [We were] extremely desperate...her life depended on it," she said.
The girl said she believes the man isn't done with his killing spree.
"If he's doing that many murders he's not going to stop, he obviously enjoys it and he's sick in the head," she said.
Mother of Long Island Serial Killer Victim Fears for Family's Safety
Melissa Barthelemy's mother, Lynn Barthelemy, said that the family fears the killer might know what the younger sister looks like and might come after her.
"I'm afraid all the time. I always have to know where my daughter is. I constantly call her," Lynn Barthelemy said.
When the alleged killer first called the family, they thought Melissa might still be alive.
"He never said anything about what he had done to her," Lynn Barthelemy said.
The calls seemed methodical and planned out, Lynn Barthelemy said.
"They're really wasn't much to learn. It was like he knew what he was going to say... He would do the calls like he wanted them," she said.
The mother said she had no idea that her daughter was working as a prostitute.
"She told me that she was dancing in a nightclub…when she originally came to New York, she was working as a hair stylist in a salon," Lynn Barthelemy said.
Police have tracked the calls made by the killer to crowded places in New York City like Madison Square Garden and Times Square.
"It's part of the game, it's part of the fantasy, it's part of the thrill for them," said Brad Garrett, an ABC News consultant and former FBI investigator.
Making the calls in such a crowded place makes it difficult for police to use surveillance footage to track the killer.
"He used prepaid or throwaway cell phones, that he was only on the phone for perhaps up to three minutes...at least tells you he's savvy enough that if it's tracked down, it's not going to point to him," Garrett said.
It takes police three to five minutes to track a call, so the killer staying on the line three minutes or less hinders investigators.
The killer's intelligence and savvy has led some to think he might have experience in law enforcement.
"[The killer] could be law enforcement, could be a civil servant, could be a code enforcement person, could be a building inspector, could be a postman ... or it could be anyone who knows the area quite well," former New York Police Department detective Wally Zeins told ABC News.
Search for Shannan Gilbert Leads to Discovery of Eight Bodies
Police are also looking at people who have had regular or routine access to the beach where the bodies were found, and investigators are also exploring possible links to the serial killer who murdered prostitutes in New Jersey, they said.
According to one investigator familiar with the case and the behavior of serial killers, this appears to be an organized serial killer who plans methodically and is probably above average intelligence. It appears that the killer usually lures people, kills them in one place and then disposes of the body in another.
This sort of killer is often social -- not a loner -- with family, friends and what would appear to be a normal life, the investigator said.
Zeins is confident that the killer will eventually slip up.
"Whoever it is will make a mistake, and they'll get caught," he said.