Robert Durst, the infamous millionaire whose story had been highlighted on HBO's "The Jinx," has died. He was 78.

Durst's longtime attorney Dick DeGuerin confirmed the shocking news, per CNN, saying that he died in a California prison hospital months after his murder conviction. The California Department of Corrections and Rehabilitation added that the eccentric mogul died of natural causes on Monday.

Robert Durst's cause of death is yet to be determined, but the San Joaquin County's coroner would reportedly start running the tests.

Meanwhile, his other lawyer, Chip Lewis, said that the late convicted murderer suffered from several medical issues before his death. He was diagnosed with COVID-19 in October, which prompted him to have a ventilator during his sentencing hearing.

In addition, his team tried to file an emergency motion last year due to his life-threatening health issues, like his untreated bladder cancer.

"We are very concerned about his health," Dick DeGuerin said at that time. "He's been in and out of clinics and hospitals frequently."

Robert Durst and His Crime

The New York real estate empire's heir was accused of killing his close friend, Susan Berman, in the head inside her Beverly Hills home on Dec. 23, 2000. He reportedly murdered his friend due to her knowledge of the disappearance of his first wife, Kathleen.

The woman was last seen alive in January 1982, and it took decades before he was finally found guilty of first-degree murder. Despite his conviction, Kathleen's family has since broken their silence said they wanted more justice for their family member.

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Meanwhile, Berman's body was discovered after a neighbor noticed that her dogs were loose. While Durst strongly denied he was in Los Angeles during his friend's death, Los Angeles County Deputy District Attorney John Lewin said Berman was killed by the person she trusted the most.

But aside from Berman and his first wife, he was also reportedly responsible for the death of his neighbor, Morris Black, in Texas. Durst first insisted that he only did self-defense after his neighbor allegedly pointed a gun at him and that Black died when they argued over the weapon.

Despite his continuous denial, the HBO documentary revealed his behavior and included a recording where he said he killed them all.

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