A former medical student who killed himself while awaiting trial in the shooting death of a masseuse he met through Craigslist used his blood to scrawl his former fiancee's name on the wall of his Boston jail cell.

Sources told MyFOXBoston.com that Philip Markoff slashed his ankles and neck and used his blood to write the words "pocket" and "Megan" on the wall of the Nashua Street jail cell, an apparent reference to his former fiancée, New Jersey medical student Megan McAllister. It was unclear what the word "pocket" referred to.

Jailhouse sources told the Boston Herald that Markoff, 24, used a shank fashioned from a pen and put a plastic bag over his head to end his life. No suicide note was found.

Corrections officers are now reportedly fearful that they'll be scapegoated for the high-profile death as officials launched a probe into the apparent suicide.

"(Officers are ripped because they think they dotted the I's and crossed the T's," one source close to the Suffolk House of Corrections officers' union told the Herald, requesting anonymity. "Their concern is that they're going to be become scapegoats."

The source continued, "[Markoff] probably shouldn't have been taken out of the psych ward. Here was a guy that kept saying he was going to kill himself. He was hell-bent on doing it."

Authorities completed an autopsy Monday but were waiting for the results of specialized tests before releasing the cause of death.

Family members of slain masseuse Julissa Brisman were angry they won't have the chance to confront Markoff at trial and hear the details of their loved one's final moments, said a lawyer for Brisman's mother, Carmen Guzman.

"First he took their daughter from them, then he denied that opportunity for them," said the lawyer, Djuna Perkins. "The criminal trial allows them to confront the suspect, hear the evidence and reach some resolution in the case."

Markoff was arrested in April 2009 on charges of binding, beating and shooting the 26-year-old Brisman with a gun that prosecutors say he later stashed in a hollowed-out anatomy textbook. He became instant tabloid fodder and a cover story in People magazine.

"It has sex, it has enigma, it has the story of a respectable, smart, success-oriented, helpful young man who, without warning, becomes a killer, and that is why people pay attention to it," said Jack Levin, a professor of sociology and criminology at Northeastern University in Boston who has written books on murder.

Authorities charged him in two other attacks -- including the armed robbery of a Las Vegas woman at another Boston hotel and the assault of a stripper inside a Rhode Island hotel where authorities found his fingerprints on the wall. The three crimes occurred within a week.

Markoff was taken into custody during a traffic stop as he and McAllister were driving to Foxwoods Resort Casino in Connecticut, six days after he allegedly shot Brisman in the Marriott Copley Place Hotel in Boston's historic Back Bay district. Authorities say he lured her and botched a robbery to support a gambling habit.

His expressionless demeanor during his first court appearance was a stark contrast from his broad smile in a 2007 photograph taken as he donned a white coat at a ceremony for incoming medical students at Boston University.

His personal life came undone as prosecutors presented evidence they said linked him to Brisman's killing and other attacks of women who advertised in Craigslist's "erotic services" category.

McAllister, who met Markoff in 2005 while volunteering at a medical center, ended their relationship and canceled plans for a beachfront wedding. Saturday was to have been their wedding anniversary.

Markoff had pleaded not guilty in Brisman's death and was to have stood trial next March amid evidence that prosecutors said included blood stains taken from swabs on a handgun found in his Quincy, Mass., apartment.

The Suffolk County district attorney's office announced the apparent suicide Sunday but did not say how he died. Various news reports, citing unnamed sources, have said he was found with a plastic bag over his head and with stab wounds or cuts to his body.

He had been placed on suicide watch just days after arriving at the Nashua Street jail after authorities reportedly noticed marks on his neck.

Suffolk County recorded an average annual rate of 10 suicides per 100,000 jail inmates between 2000-2007, according to a report by the Bureau of Justice Statistics. Nationally, the average rate during that time was 42 suicides per 100,000 jail inmates, the report said.

Sheriff Andrea Cabal said the county books 9,000 to 10,000 inmates annually, and her guards prevent an average of 57 suicides each year. She said there have been five inmate suicides since 2003, including Markoff's.

Brisman's family may want answers, but presumably so do unsuspecting friends and former teachers of Markoff, who describe him as generally well-behaved and studious while growing up in New York state.

He was on the golf and bowling teams at Vernon-Verona-Sherrill High School and belonged to the National Honor Society. He graduated from the State University of New York-Albany.

"He was a very polite, courteous, just kind of ordinary boy-next-door," said Sonja Hulks, a former neighbor who was Markoff's 11th-grade English teacher. "He was always smiling, friendly, seemed just very good-natured."

When she learned of the accusations against him, she said, "I just thought it was some other Phil Markoff."

With Markoff dead, Levin said, any attempt to explain motivation or reconcile wildly contrasting images -- aspiring doctor versus cold-blooded killer -- will likely be futile.

"The suicide puts an end to a lot of the publicity, but it also increases the interest at one level because it gives the public another mystery," Levin said. "There are plenty of mysteries to go around in this case."

The Associated Press contributed to this report.

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