Question: How did the subject of the 2015 Austrian thriller film "Jack" die?

full_context: Document 1: Jack Unterweger: Johann "Jack" Unterweger (16 August 195029 June 1994) was an Austrian serial killer who murdered prostitutes in several countries. First convicted of a 1974 murder, he was released in 1990 as an example of rehabilitation. He became a journalist and minor celebrity, but within months started killing again. He committed suicide following a conviction for several murders. Austrian psychiatrist Dr. Reinhard Haller diagnosed him with narcissistic personality disorder in 1994.
Document 2: Grim Sleeper: Grim Sleeper is the nickname for convicted serial killer Lonnie David Franklin Jr., responsible for at least ten murders and one attempted murder in Los Angeles, California. The attacker was dubbed the "Grim Sleeper" because he appeared to have taken a 14-year break from his crimes, from 1988 to 2002. In July 2010, Franklin was arrested as a suspect, and, after many delays, his trial began in February 2016. On May 5, 2016, the jury convicted him of killing nine women and one teenage girl. On June 6, 2016, the jury recommended the death sentence, and on August 10, 2016, Los Angeles Superior Court sentenced him to death for each of the ten victims named in the verdict.
Document 3: Play the Game (2015 film): Play The Game! is a 2015 Austrian mystery thriller film portraying a series of events which take place in the context of a real-life game. It was written and directed by Jörg Helbig. The film uses elements of film noir and psychological thriller. It opened in Austria on June 16, 2015.
Document 4: Jack Kevorkian: Jacob "Jack" Kevorkian ( ; May 26, 1928 – June 3, 2011) was an American pathologist and euthanasia proponent. He is best known for publicly championing a terminal patient's right to die via physician-assisted suicide; he claimed to have assisted at least 130 patients to that end. He was often portrayed in the media with the name of "Dr. Death"; however, many consider him a hero, as he helped set the platform for reform. He famously said, "Dying is not a crime".
Document 5: Jackals (2017 film): Jackals is a 2017 American horror-thriller film directed by Kevin Greutert and produced by Tommy Alastra. The film is written by Jared Rivet.
Document 6: Jack Torrance: John Daniel Edward "Jack" Torrance is the main antagonist of Stephen King's horror novel "The Shining" (1977). He was portrayed by Jack Nicholson in the novel's 1980 movie adaptation and by Steven Weber in the 1997 miniseries. The American Film Institute rated the character (as played by Nicholson) the 25th greatest film villain of all time. In 2008, Jack Torrance was selected by "Empire Magazine" as one of "The 100 Greatest Movie Characters". "Premiere Magazine" also ranked Torrance on their list of "The 100 Greatest Movie Characters of All Time".
Document 7: Jack (2015 film): Jack is a 2015 Austrian thriller film about serial killer Jack Unterweger, directed by Elisabeth Scharang. It was screened in the Contemporary World Cinema section of the 2015 Toronto International Film Festival.
Document 8: 1915 (film): 1915 is a 2015 psychological thriller film co-written and directed by Garin Hovannisian and Alec Mouhibian. It is produced by Hovannisian and Mouhibian with Terry Leonard, and stars Simon Abkarian, Angela Sarafyan, Samuel Page, and Nikolai Kinski, along with Jim Piddock. "1915" follows a mysterious theater director in present-day Los Angeles as he stages a controversial play to bring the ghosts of a forgotten tragedy back to life. The title refers to the Armenian Genocide. The film also features the first original film score by Serj Tankian, the Grammy-winning frontman of System of a Down.
Document 9: Charles Sobhraj: Sobhraj is widely believed to be a psychopath. He was driven to murder as a means to sustain his adventurous lifestyle. This, as well as his cunning and cultured personality, made him a celebrity long before his release from prison. He enjoyed the attention, charging large amounts of money for interviews and film rights. He has been the subject of four books and three documentaries. Sobhraj's return to India, where he was still eagerly sought by authorities, is believed to be the result of his yearning for attention and overconfidence in his own intellect.
Document 10: Jackrabbit (film): Jack Rabbit is a 2015 American cyberpunk film directed by Carleton Ranney, who co-wrote it with Destin Douglas. Josh Caras and Ian Christopher Noel star as residents of a dystopian city who attempt to find details about the death of their mutual friend, a computer hacker. It premiered at the 2015 Tribeca Film Festival.
Document 11: Killer: A Journal of Murder (film): Killer: A Journal of Murder is a 1995 American drama film written and directed by Tim Metcalfe. It is based on the life of serial killer Carl Panzram, and uses passages from his . James Woods stars as Panzram and Robert Sean Leonard as Henry Lesser. Other stars include Ellen Greene as Elizabeth Wyatt, Cara Buono as Esther Lesser, Robert John Burke as R.G. Greiser and Richard Riehle as Warden Quince. Michael Jeffrey Woods, James Woods' young brother also made an appearance as Harry Sinclair.
Document 12: Utkarsha: Utkarsha (Kannada: ಉತ್ಕರ್ಷ ) is a 1990 Kannada movie by Sunil Kumar Desai starring Devraj. The concept of the movie is based on "Jack the Ripper". 2011 Hindi movie "Murder 2" which was unofficially based on the 2008 South Korean movie "The Chaser" also had a similar plotline.
Document 13: Sture Bergwall: Sture Ragnar Bergwall (born 26 April 1950), also known as Thomas Quick in 1993–2002, is a Swedish man previously believed to have been a serial killer, having confessed to more than 30 murders while incarcerated in a mental institution for personality disorders. Between 1994 and 2001, Quick was convicted of eight of these murders. However, he withdrew all of his confessions in 2008, as a result of which his murder convictions were quashed, the final one in July 2013, and he was released from hospital. The episode raised issues about how murder convictions could have been obtained on such weak evidence, and has been called the largest miscarriage of justice in Swedish history. Journalists Hannes Råstam and Dan Josefsson made TV documentaries and books about the murder cases; they claimed that bad therapy led to false confessions, Dan Josefsson claims that a "cult" like group led by psychologist Margit Norell manipulated the police and talked Sture Bergwall into false confessions.
Document 14: The Journalist and the Murderer: The Journalist and the Murderer is a study by Janet Malcolm about the ethics of journalism, published by Alfred A. Knopf/Random House in 1990. It is an examination of the professional choices that shape a work of non-fiction, as well as a rumination on the morality that underpins the journalistic enterprise. The journalist in question is Joe McGinniss; the murderer is the former Special Forces captain Dr. Jeffrey R. MacDonald, who became the subject of McGinniss' 1983 book "Fatal Vision".
Document 15: Jack the Ripper: Jack the Ripper is the best-known name for an unidentified serial killer generally believed to have been active in the largely impoverished areas in and around the Whitechapel district of London in 1888. The name "Jack the Ripper" originated in a letter written by someone claiming to be the murderer that was disseminated in the media. The letter is widely believed to have been a hoax and may have been written by journalists in an attempt to heighten interest in the story and increase their newspapers' circulation. In both the criminal case files and contemporary journalistic accounts, the killer was called "the Whitechapel Murderer" and "Leather Apron".
ground_truth: He committed suicide