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Weaving together cell phone records with fibers from a pair of fur-collared jackets and a rug, investigators compiled an unprecedented "CSI"-style case to charge a Manhattan bar bouncer, arraigned Thursday in the gruesome rape and murder of a Boston graduate student.

Authorities said they had also collected DNA evidence against Darryl Littlejohn, 41, who pleaded not guilty at a Brooklyn arraignment where he arrived wearing shackles and a grim look on his face. Lacking a confession or a conclusive eyewitness account, investigators used forensic evidence to build their case against Littlejohn.

Brooklyn prosecutors have "never seen a case where there has been so much forensic evidence as the foundation of a case," said District Attorney Charles Hynes. Littlejohn, a parolee with a long criminal history, has steadfastly denied any involvement in the death of Imette St. Guillen, a graduate student at John Jay College of Criminal Justice in Manhattan.

After the hearing, the sister of victim Imette St. Guillen wept as she read a statement thanking police for their efforts in tracking down a suspect. She also recalled her 24-year-old sister's love of New York City.

"New York was Imette's home," said Alejandra St. Guillen, who was joined by her mother Maureen. "She loved the city and its people ... Imette was a good person, a kind person. Her heart was full of love. With Imette's death, the world lost someone very special too soon."

The indictment unsealed Thursday marked a breakthrough in the slaying of St. Guillen, whose body was found dumped in a desolate section of Brooklyn on Feb. 25 with a white athletic sock stuffed in her mouth and her head wrapped with packaging tape.

Littlejohn was arraigned on both first- and second-degree murder charges. Hynes said he was charged with first-degree murder because the killing was allegedly committed during a sexual assault. If convicted, he faces life in prison without parole.

Hynes, joined by Police Commissioner Ray Kelly, laid out the evidence against Littlejohn, including DNA linking the defendant to blood found on ties used to bind St. Guillen. Fibers discovered on tape on the victim's head were consistent with those from a rug and two fur-collared jackets from the defendant's apartment, Kelly said.

Investigators found mink and rabbit fur on the tape. "This is an unusual finding, put it that way," Kelly said. "Two jackets. A rabbit collar and a mink collar."

Finally, investigators said cell phone transmissions show that Littlejohn's phone was used to make a call from near the spot where the body was dumped, only an hour before it was discovered. An eyewitness spotted a van resembling one belonging to Littlejohn in the same area, Kelly added.

Police said there were no witnesses or other evidence to support Littlejohn's claim that he was visiting his mother on the day of the killing.

St. Guillen was last seen alive after a late night of drinking at The Falls bar, a SoHo nightspot where Littlejohn worked as a bouncer.

A manager at The Falls has told police Littlejohn escorted St. Guillen out after she stayed sipping a drink past the 4 a.m. closing time; he recalled hearing the pair arguing before they disappeared through a side door. Sometime during the next 17 hours, the graduate student was killed.

Investigators soon set their sights on Littlejohn, a career criminal whose record includes robbery, drug and gun convictions, and locked him up on a parole violation as they slowly built their case.

In a jail interview with WCBS-TV, Littlejohn denied killing St. Guillen and said police "have the wrong person."

Asked whether he killed St. Guillen, he said, "No, I did not."

Littlejohn's first brush with the law came at age 17, when he robbed someone with a shotgun. Over the years, he was convicted on drug and gun charges using names like Darryl Banks, John Handsome and Jonathan Blaze — the name of a comic book character. He allegedly violated his parole by working at The Falls past his 9 p.m. parole curfew.