NEW YORK (AP) — Former in-laws of millionaire estate heir Robert Durst are accusing his current wife of helping him cover up the killing of his long-vanished former spouse. He’s long been suspected but never charged in her disappearance and denies involvement.

Kathleen Durst’s sisters make the claim about Debrah Charatan in court papers filed this week in New York.

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The sisters were already suing Robert Durst. He’s jailed in California on a charge of killing a friend to keep her from talking about Kathleen Durst’s 1982 disappearance.

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He pleaded not guilty in the friend’s death. He was arrested the day after the final installment of an HBO documentary about him, “The Jinx,” aired on HBO. In it, he is heard muttering that he “killed them all.”

Charatan’s lawyer had no immediate comment Wednesday.

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