Expert: Philadelphia Strangler 'Is Not Going to Stop'

DNA tests show that three women who were slain in the same section of Philadelphia were killed by the same assailant. And he may have more victims. But despite an increased police presence and national media exposure, this serial killer will continue to prey upon victims, an expert told AOL News today.

"A guy like this is not going to stop because he is already engaged in high-risk behavior by operating in very short time spans over a small geographic area," said Mark Safarik, a retired FBI supervisory special agent.

"There is no reason for him to stop at this point," Safarik said. "He may move to a different area, but it sounds like he is fairly comfortable in this location."

Safarik and his partner, retired FBI agent Robert Ressler, are the founders of Forensic Behavioral Services International, a 16-year-old company that provides expert opinion and analysis to law enforcement agencies, attorneys, Fortune 500 companies and foreign entities.

The three cases that have been linked together are the slayings of Casey Mahoney, 27, Elaine Goldberg, 21, and Nicole Piacentini, 35.

On Tuesday, authorities confirmed public suspicion that the cases were linked. DNA evidence was used to make the connection, police said.

"We now know that this predator is responsible for three murders in this area," task force Capt. James Clark said at a news conference.

Local police are working with the FBI's behavioral science experts in Quantico, Va., to develop a profile of the serial killer. Many details in the case have not been released to the public, but it is known that all of the victims are white and, at one time, were allegedly involved in prostitution and narcotics, police said.

"He is identifying the more high-risk women who are willing to go with him," Safarik said, "so their inhibitions would be quite a bit lowered than otherwise."

Goldberg, from Philadelphia, was found dead on Nov. 3 in a vacant lot on Ruth Street.

Piacentini, also from Philadelphia, was found dead less than two weeks later, on Nov. 13, in a vacant lot on East Cumberland.

Mahoney, from East Stroudsburg, Pa., was found dead on Dec. 15 in a wooded lot at Front and Tusculum streets.

All of the victims had been sexually assaulted and strangled. The victims were found partially nude, and all were found within 10 blocks of one another, police said.

Authorities are trying to determine if four recent sexual assaults when the victims were choked but survived could be connected to the serial killer. In at least two of the cases, the victims were choked into unconsciousness, police said.

"Strangulation is a tough way to kill somebody because it takes an extended period of time maintaining that pressure," Safarik said. "If the strangulations without homicides are linked, he might have choked them into unconsciousness. He probably thought they were dead and then he left."

Safarik added, "Typically, we see offenders escalating rather than de-escalating behavior, simply because they become more efficient. They get better at doing the kill. They find out what works, what doesn't."

If the attacks in which the women survived are connected to the serial killer, they could hold vital information in the case, Safarik said.

"You need to look at the kind of information you are going to get from the surviving women," he said. "You delve into the physical interaction, the sexual interaction and the verbal interaction that these women are having with this guy. It should be pretty consistent in terms of how they met up with him, and that really is going to be a big help."

Authorities have released a suspect sketch based on the descriptions of the women who survived the attacks. The assailant is described as an African-American male in his early 20s with a slender build, short hair and a small goatee.

Safarik said he typically advises against the release of a composite early in an investigation but says it could prove helpful in this case as long as all the women are in general agreement.

"My sense is that the composite that is out there is probably pretty good because you have multiple victims," he said. "He looks fairly identifiable, so people who know him really should be stepping up."

Because all the deaths and attacks took place in the same stretch of the Kensington section of Philadelphia, authorities believe the attacker is still in the area.

"We have detectives working day and night, following every tip," Clark said Tuesday.

Safarik also suspects the serial killer is local and believes he is meeting his victims on foot, something he describes as unusual.

Authorities have no suspects or people of interest in the case, but because of the serial killer's MO, authorities believe they can close in quickly, Safarik said.

"Either he is not evidence conscious or he doesn't care," he said. "My guess is, he probably doesn't care because the linkage of these women has been noted in the news, and he is operating in a pretty small geographical area. If he continues to operate in that area, it should be just a matter of time before he is caught."