LOS ANGELES (CBSLA.com) — A second man accused in the murders of five people, three of whom were also set on fire in a Quartz Hill home in 2008, has pleaded guilty as a jury was being picked for his trial.

Steve Kwon, 44, pleaded guilty Thursday to murder and arson and will face a sentence of 125 years to life in prison when he is sentenced on Aug. 21, along with his co-defendant Jae Shim, 46.

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Shim pleaded guilty Feb. 4 to the first-degree murders of Shim’s 34-year-old ex-wife, Jenny Young Park; her daughter, Jamie, 13, her 11-year-old son, Justin; Park’s cousin and NASA scientist, Joseph Ciganek, 60; and Park’s boyfriend, Si Young Yoon, also 34. Shim was set to testify against Kwon as part of his plea deal.

Shim also admitted the special circumstance allegations of lying in wait and multiple murders and that he personally used a samurai sword and baseball bat to stab and beat his ex-wife and the other victims to death in Ciganek’s home.

Both men also pleaded guilty to one count of arson of an inhabited structure.

Shim faces five consecutive life terms without parole, but avoided a possible death sentence as a result of his plea.

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The five victims were stabbed and bludgeoned to death on June 23, 2008. The two children, along with their mother, also were set on fire.

Deputy District Attorney Beth Silverman with the Major Crimes Division said Shim became enraged that his ex-wife was recently engaged to Yoon.

Shim enlisted the help of Kwon, a lifelong friend from Korea to murder the victims. Ciganek’s wife was also an intended victim, but survived because she was not home when the crimes occurred.

As part of his plea agreement, Shim helped lead authorities to the remains of Yoon, whose body had been dumped in Mexico.

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