SAN DIEGO -- The family of a woman whose nude, bound body was found hanging at a California mansion has filed a $10 million lawsuit claiming she was murdered.

The suit was filed Friday in federal court by the family of 32-year-old Rebecca Zahau and seeks general and punitive damages. Zahau was found hanged at a Coronado mansion in July 2011. Her death was ruled a suicide.

But Zahau's family always believed her death was suspicious. The lawsuit claims Adam Shacknai and Dina Shacknai, the brother and ex-wife of Zahua's boyfriend, Jonah Shacknai, and Dina Shacknai's twin sister, Nina Romano, were responsible for the woman's death. The filing of the lawsuit was first reported by U-T San Diego (http://bit.ly/1aD6eO9).

The lawsuit doesn't provide any specific evidence against the three, but alleges "defendants planned and prepared to batter and murder Rebecca and did thereafter brutally, and with malice aforethought, stalk, attack, choke, bound and hang" Zahau at the mansion belonging to her billionaire boyfriend. Jonah Shacknai was not named in the lawsuit.

No criminal charges were filed.

Attempts to reach Adam Shacknai, Dina Shacknai and Nina Romano on Sunday were unsuccessful.

Authorities said Zahau killed herself because she was distraught over a fatal fall that Shacknai's 6-year-old son suffered at the house two days earlier. His death was ruled accidental.

Adam Shacknai was staying in a guesthouse at his brother's historic Spreckels mansion at the time of Zahau's death, the U-T reported. Dina Shacknai was staying in a separate vacation home a few blocks away, and Nina Romano had flown in from Sacramento to be with her sister.

Adam Shacknai told police he found Zahau hanging by a rope from a second-story balcony at the mansion, and cut her down. Her hands were bound behind her back, her feet were bound and a T-shirt was wrapped around her lower face.

The remodeled mansion was sold last month for $9 million to the owner of a private aircraft company in Utah.

Earlier on HuffPost:

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  • Flowers and messages adorn a flower box outside the Spreckels Mansion in Coronado, Calif. Monday, July 18, 2011. The mansion is the site where a woman was found dead July 13, she was hanging nude from a balcony with her hands and feet bound. Credit: Lenny Ignelzi, AP

  • This 2010 photo released by Medicis Pharmaceuticals Corp. shows CEO Jonah Shacknai. Shacknai's 6-year-old son and 32-year-old girlfriend have each died in a span of less than a week, and both deaths were tied to his historic mansion on the San Diego Bay. Credit: Medicis Pharmaceuticals Corp. / AP

  • This August 2008 photo released by Horizon Eye Specialists & Lasik Center shows Rebecca Zahau, also known as Rebecca Nalepa, 32. Nalepa, the girlfriend of Arizona pharmaceuticals tycoon Jonah Shacknai, was found dead last week hanging nude from the second-floor balcony of a historic mansion, her wrists and ankles bound. Credit: Dwight Smith, Horizon Eye Specialists & Lasik Center / AP

  • This photo family released on Sunday, July 17, 2011 shows his 6-year-old Max Shacknai. Shacknai, son of Medicis Pharmaceuticals CEO Jonah Shacknai, has died, almost a week after falling down the stairs at his father's San Diego-area mansion, the same house where his father's girlfriend was found dead hanging nude from a balcony two days later. Credit: Family Photo / AP