The daughter of a wealthy Saudi businessman, Adham was inside the North Palm Avenue residence of Scott Ruffalo when he was shot once in the head on Dec. 1, 2008. The 29-year-old hairdresser clung to life for a week before succumbing to the wound.

The exact cause of Adham's death at the age of 29 has not been released pending the outcome of toxicology tests, which should be completed soon, authorities said.

Shaha Mishaal Adham, who was arrested and subsequently released in connection with the Ruffalo homicide investigation, died Jan. 6 after being admitted to Cedars-Sinai Medical Center, according to the Los Angeles County coroner's office.

A key figure in the Beverly Hills police investigation into the 2008 shooting death of actor Mark Ruffalo’s brother, Scott, has died, authorities said Wednesday.

Adham and her boyfriend, Brian Scofield, were quickly identified as persons of interest in the case. The couple turned themselves in to police a week after the shooting and were booked on suspicion of attempted murder before being released.

Since then, Beverly Hills police have said little about Ruffalo's death. Through a department spokesman, they declined to discuss what role, if any, Adham or Scofield played in the death or how Adham's death could affect the murder investigation.

"I can't comment on an open investigation or what impact, if any, the death of this individual will have on the case," said Beverly Hills Police Lt. Mark Rosen.

Coroner's officials classified Ruffalo's death as a homicide and said there were differences between the injuries to the hairdresser and witness statements. Rosen said Beverly Hills police are "actively investigating" the case as a murder.

Attorney Ronald Richards, retained by Adham after her arrest, said at the time that his client was at Ruffalo's apartment to pick up the keys to her Range Rover when Ruffalo mentioned something about "Russian roulette." Then she heard a gunshot.

Adham and another man in the apartment found the hairdresser on the couch bleeding from the left side of his head, the gun in his left hand, then left the apartment, Richards said.

Beverly Hills paramedics arrived and took the critically injured Scott Ruffalo to the hospital. Police arrived 20 minutes after the shooting to find no one at the scene, Richards said.

Even with the lack of public developments, Ruffalo's death has continued to draw considerable attention because it is unsolved and because the victim is the brother of Mark Ruffalo, who has starred in such movies as "You Can Count on Me," "Zodiac" and "Eternal Sunshine of the Spotless Mind."

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-- Andrew Blankstein

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Photo: Mark Ruffalo in 2003. Credit: Evan Agostini / Getty Images