Professor killed his wife and daughter with yoga ball leaking carbon monoxide that was left in car boot in Hong Kong

HONG KONG — A university professor who was having an affair filled a yoga ball with dangerous gas to kill his wife and daughter, a Hong Kong court heard on Wednesday (Aug 22).

Khaw Kim-sun, who specialised in anaesthesiology, put the leaking inflatable containing carbon monoxide in the boot of a yellow Mini Cooper driven by his wife, Wong Siew-fung, 47, on May 22, 2015, prosecutors told the High Court.

His 16-year-old daughter Khaw Li-ling was in the passenger seat.

Prosecutor Andrew Bruce SC said the gas, while present in everyday life, could impair vision and cause unconsciousness and death, when inhaled in sufficient volume.

"It can kill," Mr Bruce said. "And it did kill."

Both wife and daughter were certified dead in hospital after they were pulled from the car parked 20 minutes away from their home on Sai Sha Road in Sai Kung.

Khaw, then an associate professor at Chinese University's Department of Anaesthesia and Intensive Care, pleaded not guilty to two counts of murder.

Mr Bruce opened his case by telling the jury of five men and four women that Khaw would have known the effects of the gas given his educational background.

The anaesthesiologist set up a research project with "no value" to obtain the carbon monoxide he later used in the murder plot and was assisted in this project by the student he was having an affair with, Mr Bruce said.

According to the prosecutor, the daughter and wife were spotted at 3.15pm by a jogger, who thought they were "taking a nap". She called police after returning 45 minutes later and noticing they were still there.

A postmortem found they died from inhaling carbon monoxide, but the car showed no defects, which led officers to shift their attention to a deflated yoga ball in the back of the vehicle.

"First of all, who put it there? And when was it placed there?" Mr Bruce said.

Khaw was spotted by colleagues taking carbon monoxide home from the research laboratory, claiming he wanted to test its purity.

He said Khaw knew the risk and put a meter in his car when he took two yoga balls, filled with carbon monoxide, home.

During a police investigation, Khaw said he took the gas home to kill rats, "a lame excuse", according to the prosecution.

"It is simply untrue," Mr Bruce said.

"The last thing the accused wanted was for his 16-year-old to die," Mr Bruce said. Khaw had not been aware his daughter was away from school on the same day he planned to kill his wife.

"(But) if that person knew what was in the car was carbon monoxide and knew it was a dangerous gas likely to kill you, you can confirm this person had homicide on his mind," Mr Bruce told the jury.

The trial continues this afternoon before Mrs Justice Judianna Barnes Wai-ling. SOUTH CHINA MORNING POST

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