L.I. killer may know law enforcement tactics

Police on New York's Long Island are still on the hunt for a serial killer, after four more bodies were found on a desolate stretch of beach last week.

Four bodies were found in the same area in December, and authorities were to expand the area of beach they're combing through. The eight bodies were discovered in a three-mile radius.

Now, reports CBS News correspondent Seth Doane, there's word a man has made seven taunting phone calls from one of the victim's phones to a victim's family, and investigators say they have some clues that point to a suspect who may be familiar with law enforcement techniques, and how an investigation would unfold.

But a leading criminologist is downplaying that theory.

Police, says Doane, believe the killer may have made several phone calls to the sister of one of the victims, calling from busy places around New York City, such as Penn Station, so that, even if captured on a surveillance camera, the killer would be difficult to identify. And, the calls were kept short, so they'd be tough to trace.

During one call, an unidentified man asks, "Do you know what your sister is doing? She's a whore."

Dr. Lawrence Kobilinsky, a crime scene analyst and professor at the John Jay College of Criminal Justice in Manhattan, told "Early Show" co-anchor Chris Wragge Monday he's "not really convinced" the killer has law enforcement ties or knowledge, saying, "I think anybody watching programs like 'CSI' would be familiar with the fact that you shouldn't stay on a cell phone for more than three minutes or else you might be traced. So I think he's taking evasive action."

The killer, Wragge pointed out, has been very meticulous.

"I think he's smart enough to know that he shouldn't leave any kind of remnants of himself like cigarette butts or soda cans," Kobilinksy explained, "anything that might give away his identification through fingerprints or DNA. He is definitely thinking about what he's doing. He's careful."

The reported calls, Kobilinsky admits, "surprised me. Because we hadn't heard anything about taunting. There are serial killers that taunt the police, by expressing to the police, 'I'm smarter than you are. I'm one step ahead of you.' This is the first time we're hearing about taunting of family members. This fellow really has some psychological problems and he's trying to send a message to the family. It's degrading, basically.

"It sounds to me," Kobilinsky continued, "like he's a psychopath. He's fantasizing. Some of it has to do with sex. But, I think the real thrill that he gets is in the kill. You know, he fantasizes. He captures a woman through craigslist. That's the mechanism that he attracts these women. And then kills them someplace where he's very comfortable, and then deposits the body in a place that's quite desolate."

As for a published report that one of the bodies found most recently may be that of a child or baby, Kobilinsky says, "It does change the game. I mean, we have to try to determine what the motivation is for that. This is an outlier. It's unusual that a serial killer would go after young women, and now find there's a body of a young child. It's not really clear what the motivation was for the killing of the child."

Former New York Police Detective Wally Zeins observed to CBS News that, "What you look for is the common denominator, and the common denominator right now is prostitutes, and also, Craigslist."

The four victims found in the last two weeks are still unidentified, but the first four victims were strangled to death. All were women in their 20s, who advertised escort services on Craigslist, and had been missing as far back as 2007.

Zeins says the fact that those bodies were wrapped in burlap bags may be a clue. "You have to take into consideration -- who would use burlap in that area? Well - clam diggers."

Police are said to be reviewing area clamming licenses and traffic tickets.

Doane says cops think the killer is thriving on all the attention he's been getting.