The son of an Emmy-winning producer who was accused of brutally killing his wife and her parents has been found dead in his prison cell, authorities have confirmed, just days before he was meant to be appear in court for his triple murder trial.

Samuel Bond Haskell IV was facing three counts of murder following the disturbing discovery of his wife, Mei Haskell’s torso in a dumpster near his office in November 2023.

He was also charged with the murders of Mei’s mother Yanxiang Wang, and her stepfather, Gaoshan Li, whose bodies have never been found.

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The 37-year-old pleaded not guilty to all three murder charges in January 2024 and was being held in custody while awaiting trial.

On Saturday morning, Haskell was found dead in his jail cell in what law enforcement believe was suicide, according to The Daily Mail.

Los Angeles District Attorney Nathan Hochman was outraged upon learning the circumstances of Haskell’s death, describing it as “one last cruel act by someone who did the most horrific things for reasons we will never entirely know.”

“Instead of standing before a judge and answering for the crimes he’s been charged with, the defendant managed to escape justice,” Mr Hochman said in a statement on Monday.

“A family that has been dealing with unimaginable loss has now been robbed of their chance to face him, hold him accountable for his barbaric actions, and openly share their grief and their cherished memories of their loved ones.”

Mei and her parents were last seen alive on November 6, 2023.

The following day, Haskell was caught on camera allegedly dumping the contents of a bag into a dumpster near his office in Encino, California.

Police also believe Haskell hired labourers to remove three large garbage bags from his residence.

One of the labourers reportedly opened one of the bags and spotted what appeared to be human remains.

Horrified, the workers returned the bags to the home and left the scene after calling police, but the remains were gone by the time officers arrived.

A day later, a woman’s torso, was found by someone rummaging through the garbage, which led to Haskell’s arrest.

While the bodies of Mr Li and Ms Wang have never been discovered, blood inside the Haskell family home were in line with murder and dismemberment, according to authorities.

Haskell is the son of a top Hollywood producer and agent, who has worked with many stars including George Clooney, Dolly Parton and Whoopi Goldberg.