Victim's family and friends leave the New South Wales Supreme Court in Sydney, Dec. 16, 2025. Dan Himbrechts/AP

A judge sentenced a Sydney taekwondo instructor on Tuesday to life in prison without possibility of release for murdering a 7-year-old student and the boy's parents.

Kwang Kyung Yoo, 51, sat with his head bowed as Justice Ian Harrison said he would never be eligible for parole.

The former instructor, who was called Master Lion by his students, did not look at the victims' family as they cried in court, 9News Australia reported. He held a Bible stuffed with notes during the sentencing, the Sydney Morning Herald reported.

Harrison said Yoo has been motivated by the jealousy he felt for the family's financial success.

"I'm satisfied that the level of culpability in the commission of these offenses is so extreme that the community interest in retribution, punishment, community protection and deterrence can only be met through the imposition of a life sentence," Harrison told the New South Wales Supreme Court.

Harrison said Yoo had no reason to murder the boy or his parents in February last year.

"These killings were horrific and violent acts, senselessly cruel and cynical, perpetrated without a trace of human compassion or consideration for the dignity of the Cho family," Harrison said, according to news.au.

State law prevents child victims of crime from being identified, so the boy's parents also can't be named.

Yoo and his victims were all born in South Korea.

Yoo had pleaded guilty to the three murders at an earlier court appearance. He had no prior criminal record.

Yoo had strangled the boy and his 41-year-old mom in his Lion's Taekwondo and Martial Arts Academy in western Sydney. He owed tens of thousands of dollars at the time and was behind in rent on the academy.

He took the mother's Apple watch and drove her luxury BMW car to the family home where he stabbed the boy's 39-year-old father to death.

Yoo was injured in the struggle in the home and drove himself to a hospital where he told medical staff he had been attacked in a supermarket car park. Police arrested him at the hospital.

After his arrest, Yoo could not explain how he intended to get the family's money and later detailed his remorse.

While the crimes were planned — with Yoo surveilling the family's home beforehand — he made no attempt to conceal his crimes from the CCTV cameras in his academy or try to conceal the bodies.

The judge heard Yoo had lied about qualifying for the 2000 Olympics, owning a Lamborghini and living in Sydney's wealthy suburbs, 9News Australia reported. He would send emails to himself, pretending to be important people, in order to impress his wife, the outlet reported.

Harrison noted that Yoo had told a psychologist his lies became bigger and bigger as his wife and students asked more questions.

"I wanted to give her hope," he told his psychiatrist, according to the Sydney Morning Herald. "However, over time it became bigger and bigger and didn't stop. She was so happy."

The judge noted Yoo had been burdened since childhood with unrealistic expectations from his parents and South Korean culture about the level of success he needed to achieve.

Yoo was handed a box of tissues as the judge described his deep remorse for the hurt and pain that he had caused.

In a letter to the judge, Yoo said he was "held captive by sin" and that he wanted to give himself to Jesus Christ.

"I wish I could turn back time so this didn't happen," Yoo wrote. "I pray every day for the people I have hurt."

Yoo's lawyers had argued that he should be given a minimum nonparole period rather than a life sentence without possibility of release. The maximum penalty for someone convicted of murder in New South Wales is life imprisonment, with a standard nonparole period of 20 years for the murder of an adult and 25 years for the murder of a child.

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