On the afternoon of 17 September 1972, 22-year-old Malaysian seamstress Chan Chee Chan was walking along Commonwealth Avenue towards Queen's Circus in Queenstown, Singapore, with her younger sister Kim Moy, when she suddenly cried out in pain. Her sister initially believed she was suffering from a stomachache and offered her medicated oil, but Chan collapsed as blood began oozing from a wound on her left chest. She had been struck by a .22 calibre bullet fired from a distance of at least 30 feet at an angle of 30 degrees to the left, believed to have come from inside one of the nearby 16-storey Housing Board flats.
Chan was taken by ambulance to Outram Hospital (now Singapore General Hospital). Police officers attended to take her statement, but she remained unconscious and died several hours later. A .22 calibre bullet was subsequently extracted from her chest.
As part of the investigation, police seized nine rifles and one pistol from licensed gun owners in the vicinity of Queenstown and test-fired them, but none matched the fatal bullet. Six witnesses who had heard the gunshot came forward, including one with firearms experience who believed the shot had come from a rifle. Chan's family described her as living a quiet life with no known enemies. However, investigators considered a theory that her sister Kim Moy, who was walking with her at the time, may have been the intended target, and that the gunman could have been a rejected suitor or a hired killer.
A coroner's hearing into the shooting was held in March 1973. Police firearms specialist Assistant Superintendent Lee Ah Fong testified that silencers were not commercially available in Singapore at the time, but that the gunman could have fabricated one. Inspector Ng Ah Kow, the investigating officer, confirmed that firearms seized from nearby residents had been test-fired with no match found. The coroner returned an open verdict.
In the days following the shooting, Chan's sisters went into hiding and locked up their family flat in Tanglin Halt, citing the possibility that Kim Moy had been the actual target. The case was never solved and no suspect was ever charged.
In 2022, the case was featured in the fifth episode of the first season of the Chinese-language crime series Inside Crime Scene.