On 25 April 1978, Lee Kim Lai (Chinese: 李金来; pinyin: Lǐ Jīnlái), a Singaporean police officer, was robbed and murdered by three men for his service revolver.

His body was later found with multiple stab wounds in the abandoned taxi, whose driver, 60-year-old Chew Theng Hin, had also been killed earlier.

The last of the three, a school drop-out at age 12 after repeatedly failing his Entrance Examination in 1972, had worked as a painter and an odd job labourer.

The second-oldest child in a family of five siblings, Lee Kim Lai, aged 18, was attached to the Police Reserve Unit 1 at Mount Vernon for his National Service.

On the night of 21 April 1978, the three friends gathered at a playground in Geylang Bahru to discuss a solution to the economic hardship that the three were experiencing.

On 24 April, they proceeded to pawn Chin Hock's watch in exchange for cash to buy two kitchen knives at about 9:00 pm, which Hwee Kuan felt were necessary to threaten the policemen.

Yeo, particularly wary that they may be searched by patrolling policemen, brought the knives home, where he packed them together with four yellow nylon ropes, an ice pick and a pair of gloves in a traveling bag belonging to his brother.

At 11:45 pm, they met for a final meal at Kallang Bahru, where Yeo proposed an alternative plan to steal a taxi.

Chew was instructed to stop the taxi near the rear gate of the PRU base at a dark and secluded stretch of the road.

He tied the driver with the nylon ropes and ordered him out of the taxi, when Chew suddenly attempted to break free from the aggressors.

Yeo and Hwee Kuan stabbed the man in the neck with the ice pick and knife respectively causing Chew to fall back into the drain.

The front seat passenger, Yeo, alighted from the taxi with the ice pick hidden in his waist and approached the sentry, flashing his NS Police Warrant.

Yeo helped to push the struggling man in, slammed the door shut and quickly returned to his front seat.

[5] Yeo noticed what appeared to be figures looking in his direction from the police quarters and hurriedly asked Chin Hock to leave.

As the taxi sped away along Upper Aljunied Road, Hwee Kuan stabbed the knife into Lee's neck and removed his revolver which was handed over to Yeo.

Chin Hock was instructed to stop the taxi five minutes later at Kallang Bahru, where Yeo rummaged the dead policeman's uniform and retrieved all ten rounds of ammunition.

Later, in the vicinity, off-duty police officer Constable Siew Man Seng (Chinese: 萧万成) spotted Yeo and Hwee Kuan behaving suspiciously.

[6] Four hours later, the taxi driver Chew was also found dead in a drain near the Mount Vernon base with a stab wound in the abdomen.

The following day, at a flat in Kallang Bahru, Yeo was arrested and Lee's service revolver and ten bullets were recovered.

Yeo was represented by Ram Goswami, Hwee Kuan by Loh Lin Kok, and Chin Hock by Alfred Tan.

[24][25] Shortly before their executions, the trio were allowed to have a last meal (although the exact order of food is unknown), and Yeo offered to donate his eyes.