( CNN ) -- A onetime medical student who was facing charges including first-degree murder in a killing tied to the Craigslist website died Sunday of an apparent suicide , police said . Philip Markoff was found unresponsive in his Boston , Massachusetts , jail cell at 10:17 a.m. Sunday and pronounced dead by medics , according to officials . The cause of death is under investigation , Boston Police Commissioner Edward Davis and Suffolk County District Attorney Daniel F. Conley said in a statement . `` Markoff was alone in his cell and all evidence collected thus far indicates that he took his own life , '' the statement said . `` Nonetheless , as with all such cases , a comprehensive investigation will be conducted to determine the facts and circumstances surrounding his death . '' An autopsy is scheduled to be conducted Monday , according to Jake Wark , a spokesman for Conley . Markoff , 24 , was charged with the April 14 , 2009 , fatal shooting and attempted robbery of Julissa Brisman , 25 , at Boston 's Copley Marriott Hotel . Police said that Brisman , a model , advertised as a masseuse on Craiglist , a popular online classifieds service , and said Markoff may have met her through the site . In a statement Sunday , the family of Brisman said it was `` shocked and dismayed '' at the news of Markoff 's apparent suicide . `` Their grief for Jullissa is as fresh today as the day over a year ago when Markoff took Julissa away from them , '' said the statement issued by a representative for the family . `` The long-awaited criminal prosecution was their only opportunity to confront him , and now he has taken that away as well . '' The family promised to pursue `` other avenues to seek justice for Julissa and help ensure that others do not suffer from such devastating , unnecessary violence , '' according to the statement . Markoff was also charged with the April 10 , 2009 , robbery of Trisha Leffler at a Westin Hotel in Boston . Police reports said Leffler was robbed of $ 800 in cash and $ 250 in American Express gift cards and was held at gunpoint and bound . At his arraignment in June 2009 , Markoff pleaded not guilty to the Massachusetts charges . He also was facing charges in an April 16 , 2009 , incident at a Holiday Inn Express in Warwick , Rhode Island . In that incident , police said Markoff tied up and demanded money from a 26-year-old dancer who had posted a Craigslist advertisement . The robbery was interrupted when the woman 's husband entered the room , and the suspect fled after pointing his gun at the husband , according to Warwick Police Chief Col. Stephen McCartney . At the time of his April 2009 arrest , Markoff was a second-year student at Boston University 's School of Medicine and was engaged to be married . His friends and acquaintances expressed shock , describing him as a model student and the `` all-American '' guy . A woman identifying herself as Megan McAllister , his fiancee , maintained his innocence in an April 2009 e-mail sent to ABC News , saying Markoff `` is the wrong man '' and `` was set up . '' `` Unfortunately , you were given the wrong information as was the public , '' she said . `` All I have to say to you is Philip is a beautiful person inside and out and could not hurt a fly ! '' Markoff 's attorney had also proclaimed his innocence . Suffolk County District Attorney Daniel Conley told reporters last year that Brisman 's death was `` a brutal , vicious crime -- savage . And it shows that Philip Markoff is a man who 's willing to take advantage of women -- to hurt them , to beat them , to rob them . '' Brisman sustained blunt head trauma , and was shot three times at close range , prosecutors said . Conley said they believe the motive for her death was robbery . In executing a search warrant at Markoff 's home , police found a firearm , along with restraints and duct tape , he said . Surveillance videos from the hotel where Brisman was killed showed a tall , clean-cut young blond man in a black windbreaker leaving the property , according to Boston police , who had sought public assistance in identifying the man . Police traced the Internet communications with Brisman to an e-mail account that had been opened the day before her death , Conley said . Using Internet provider information , they found the computer was at Markoff 's residence in the Boston suburb of Quincy , he said . Authorities put the home under surveillance , Conley said , and `` the case just begins to build from there . '' CNN 's John Branch and In Session 's Beth Karas contributed to this report .
NEW : Family of victim says it is `` shocked and dismayed '' at the news . Philip Markoff was pronounced dead in his jail cell . Markoff was accused of killing one woman and robbing two others . Authorities believed he met his victims on Craigslist .