An envious martial arts instructor who once lied about competing in the Olympics has learnt his fate for viciously murdering two parents and their seven-year-old son.
Kwang Kyung Yoo strangled a 41-year-old mum and then the young boy in his studio at North Parramatta in western Sydney in February 2024.
He drove the woman's BMW to the family's home in Baulkham Hills and fatally stabbed the 39-year-old father.
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The Taekwondo teacher formerly known as Master Lion sat with his head bowed in the NSW Supreme Court today as he was hit with a life sentence for his crimes.
The 51-year-old did not look at the victims' family and other supporters as they sobbed in the court's public gallery after the extreme sentence was handed down.
Justice Ian Harrison found the three murders were objectively very serious, motivated by a financially struggling Yoo becoming jealous of the family's success.
He set no parole date, meaning Yoo will die in prison.
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"These killings were horrific and violent acts, senselessly cruel and cynical," the judge said.
At a sentence hearing in November, the judge heard Yoo had lied about meeting Gina Rinehart, qualifying for the 2000 Olympics, owning a Lamborghini and living in Sydney's wealthy eastern suburbs.
To impress his own wife, he would send emails to himself, pretending to be important people.
In reality, at the time of his arrest, Yoo owed tens of thousands of dollars in debt and was behind on rent.
The victims cannot be identified due to NSW legal restrictions on identifying child victims of crime.
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