Taekwondo instructor unable to explain why he killed three people in Sydney

Court and family statements

The family of Min and Steven Cho told the Supreme Court that their lives have been “completely shattered” and that every day since the killings has been filled with pain and despair. They said that simply continuing to live feels like a punishment and that the joy and laughter once present in their home have been replaced by intense grief.

Min’s parents described their daughter as hopeful, caring and always smiling, and said that all her dreams were destroyed by the actions of taekwondo instructor Kwang Kyung Yoo. They asked Justice Ian Harrison to impose a firm and fair sentence that would reflect the severity of the crimes and deliver at least some sense of justice.

Min’s older brother said he struggles to find any reason to get up each morning and cannot imagine the depth of his parents’ suffering. In his statement, read to the court by a family friend, he spoke of their mother’s dressing table covered in tissues soaked with tears and asked his sister what he should now live for.

The victims and the killer

The case concerns the murders of 41‑year‑old Min Cho, her husband Steven Cho, and their seven‑year‑old son in Sydney’s north‑west. The family’s deaths occurred in February 2024 and left relatives and friends devastated, with many present in court for the sentencing hearing.

The offender, 51‑year‑old taekwondo instructor Kwang Kyung Yoo, ran a martial arts academy in North Parramatta where he was known to students and parents as “Master Lion.” He has pleaded guilty to murdering Min, Steven and their child and listened with his head bowed as victim impact statements were read aloud.

Timeline of the killings

According to agreed facts, Yoo killed Min in a back room of his taekwondo academy on the evening of 19 February 2024 while a children’s class was being held nearby. He then lured the seven‑year‑old boy into a storeroom and strangled him.

After the two killings at the studio, Yoo took the keys to Min’s BMW and drove the vehicle to the family’s home in Baulkham Hills. There he broke in, waited for Steven to return, and later that night stabbed him repeatedly in the head, neck and torso with a knife and scissors. Steven managed to resist and inflicted several stab wounds on Yoo before succumbing to his injuries.

Actions after the murders

Following the first two killings, Yoo briefly resumed teaching taekwondo classes before leaving the academy. Later that night he telephoned his wife, telling her, “The car has arrived,” a reference to the BMW he had taken.

After being wounded during the attack on Steven, Yoo told his wife that he had been stabbed and needed medical treatment. He falsely informed health workers that he had been attacked in a Woolworths car park, a story that was undermined when police checked CCTV footage and found no evidence of such an assault.

Financial and personal background

The agreed facts state that at the time of the murders Yoo was behind on rent and had about \$3,200 in credit card debt. Before the killings he lied to his wife, claiming he had secured extra work at a school that would come with a BMW, creating a false image of financial success.

Authorities also outlined Yoo’s obsession with luxury goods, status and wealth, noting that he had inspected multi‑million‑dollar properties in affluent Sydney suburbs such as Rose Bay and Vaucluse. He discussed buying a Lamborghini priced at around \$650,000 and a Bentley worth more than \$700,000 with car dealers, despite his debts.

Pattern of deception

Documents presented to the court describe how Yoo fabricated key elements of his life story to impress others. He once showed a student a photo of Sydney Harbour Bridge with a Lamborghini, falsely claiming it was the view from his home and his own car.

He also boasted of having a master’s degree and PhD in exercise science and of competing at the Olympics in taekwondo, claims later contradicted by Taekwondo Australia. The organisation confirmed that many of the accolades and achievements Yoo referred to did not actually exist.

Instructor’s lack of explanation

In court, Yoo has not provided a clear explanation for why he murdered Min, Steven and their son. The material before the court points to a mix of financial stress, status anxiety and chronic dishonesty, but no coherent justification has emerged for the scale and brutality of the violence.

Family members told the judge that no explanation could ever make sense of the loss of three lives, including a young child. They said their grief will last for the rest of their lives and that the consequences of Yoo’s acts extend far beyond the immediate victims.

“Our lives have been completely shattered. Every breath we take is painful and simply being alive feels like a punishment.”

“Mum’s vanity table is overflowing with tissues soaked in tears. I just can’t understand, Min, what should I live for?”

Author’s summary

This story shows how one instructor’s lies, greed and unexplainable violence destroyed a close family, leaving relatives in lifelong grief and forcing the court to confront the extremes of human cruelty.

ABC News — 2025-11-28