NYC Serial Killer On The Loose?

She was a young graduate student who died in a gruesome way:

The stark contrast between the promising life of 24-year-old Imette St. Guillen and her ghastly slaying last weekend, and the mystery surrounding her final hours, perplexed and alarmed investigators, who fear her killer may strike again.

St. Guillen had been set to graduate this semester from John Jay College of Criminal Justice in Manhattan. She graduated with honors from George Washington University in Washington.

"She was kind, she was loving and she wouldn't hurt anyone," her mother, Maureen, said Tuesday outside her home.

Investigators theorize the killer may have abducted St. Guillen, who witnesses said appeared to be alone when she left The Falls, the lower Manhattan bar where she was last seen early Saturday. But no suspects have been identified.

"What we've got here is a sexually sadistic pathological serial killer," criminal profiler Pat Brown tells The Early Show co-anchor Julie Chen. "And he is the scariest of them all, the Hollywood type that we see in the movies and don't really think is going to strike in our neighborhood. But he's out there," Brown says.

Investigators seeking witnesses and suspects in the St. Guillen's slaying have been studying security videotape from the neighborhood where she spent her last night out with friends, police said Tuesday.

One tape shows St. Guillen, talking to a female friend at about 3 a.m. Saturday outside Pioneer, a bar in the Bowery section of Manhattan. The two can be seen parting ways, with the friend leaving by cab, police said.

The friend later told police St. Guillen sounded fine when she checked on her by cell phone about 30 minutes later. The victim informed her friend she had moved on to another bar in the same neighborhood, police said.

Later Saturday, authorities received an anonymous 911 call from a man who gave the location of St. Guillen's body, and nothing more. Police traced the call to a public phone at a diner about a mile from where the body was discovered in a patch of weeds, and six miles from where she was last seen alive.

WCBS reporter Ti-Hua Chang reports that sources say the killer was careful and tried not to leave evidence behind. The clear tape on the victim's face did not have fingerprints, Chang says.

St. Guillen fought her attacker, breaking off several fingernails during a struggle, police sources tell The New York Daily News.

Investigators have tried to locate the caller, thinking he may have been involved in the crime and called out of remorse. They also have canvassed motels and hotels, believing the fitted, king-size floral bedspread wrapped around the body could have come from one of the establishments. So far, neither lead has panned out.

"My guess is he's been out there before and he's escalating in his crimes, which makes him more dangerous," Brown tells Chen. When asked if he would strike again, Brown said, "Absolutely. And the question is when."

The New York Daily News tabbed the killer the "Mummy Maniac," while the New York Post featured the supposed last words spoken to St. Guillen by her friend: "Are you going home?"

The Post reports that police are exploring whether a fake cab driver who sexually assaulted a woman near the site where St. Guillen's body was dumped might be the same person who raped and murdered the student. Officials are poring over the details of the cab assault, in which the driver sexually assaulted a woman at knifepoint on Lefferts Boulevard in the middle of last month's snowstorm about a mile from where St. Guillen's body was found.

In the previous assault, a man posing as a livery driver picked up a 32-year-old woman at Jamaica Avenue and Lefferts Boulevard on Feb. 12 as she was trying to get to JFK Airport in the middle of the blizzard. Although no evidence links the two incidents, police said it wouldn't be surprising if the phony hack had begun stalking women in bars.

"Anything is possible. Everything is wide open," a high-ranking police source told the Post.

Meanwhile, St. Guillen's family has appealed for the public's help in finding the killer.

"She was a beautiful girl, I mean beautiful inside also," her mother said.

The family has been dealing with the death by

"Really, what we want to do is just concentrate on the positive things and the life of my daughter and not focus on all the negative aspects," she said. "She was a beautiful girl, I mean beautiful inside also. She was kind, she was loving and she wouldn't hurt anyone."

The family earlier said it plans to establish a scholarship in her name at Boston Latin high school, where she was a 1999 graduate.

She was remembered by professors as an excellent student and who set an example for others.

"It's an ironic tragedy," said Joshua Freilich, her sociology professor at John Jay. "She had everything going for her."

St. Guillen enrolled at John Jay in 2004, initially to pursue a master's degree in forensic psychology, and was on the dean's list for 2004-05. Last fall she changed her field of study to criminal justice, school officials said.

"All I want is for them to find whoever did this," St. Guillen's ex-boyfriend Ryan Kocher, who met her at John Jay College told the Daily News. He is putting up his own money, along with a contribution from John Jay, to offer a $30,000 reward. Police say anyone with information about St. Guillen should call 1-800-577-tips.