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Solved case · 1972
Also known as Poon Sai Im's murder · Poon Sai Im's killing
The short answer
On 22 April 1972, 58-year-old provisions shop owner Poon Sai Im was robbed and killed on Pulau Ubin, Singapore, by two men, one of whom also raped her. The resulting prosecution and subsequent Privy Council appeal became a landmark ruling on the definition of murder under Singapore's Penal Code.
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Suggest coverage for 1972 Pulau Ubin murderThe case file
On the night of 22 April 1972, Poon Sai Im, a 58-year-old provisions shop owner living on Pulau Ubin, Singapore, was robbed and killed. Two men, 19-year-old Mohamed Yasin bin Hussin (alias Rosli) and 25-year-old Harun bin Ripin, had planned to rob her after learning she kept significant cash in her home. After luring Poon out of her house by disturbing her chickens, the two men seized her, forced her back inside, and pinned her down. While Harun searched the house for valuables, Yasin sat on Poon's chest and attempted to rape her. Poon became unresponsive during the assault. The two men attempted to revive her by splashing seawater on her, then threw her body into the sea before returning to mainland Singapore.
Poon's body was discovered the following day by a fisherman after her family reported her missing. An autopsy performed by forensic pathologist Chao Tzee Cheng determined that Poon had not drowned; instead, nine rib fractures — caused by compression consistent with someone sitting on her chest — led to cardiac arrest and death. Evidence of sexual assault and defensive injuries was also documented. The case went unsolved for nine months due to a lack of leads.
In February 1973, Harun was arrested on an unrelated matter and confessed to his role in the robbery, implicating Yasin. Both men were charged with murder and tried together in the High Court beginning 5 March 1974. On 15 March 1974, the court found that Harun could not be held liable for murder under common intention, convicting him instead of robbery by night and sentencing him to 12 years' imprisonment and caning. Yasin was convicted of murder and sentenced to death.
Yasin appealed to Singapore's Court of Appeal, which upheld his conviction in November 1974. He then appealed to the Privy Council in London, which on 4 February 1976 overturned his murder conviction, finding no evidence that Yasin had intended to cause the fatal injuries. The Privy Council instead found him guilty of causing death by a rash or negligent act under Section 304A of the Penal Code, and the case was remitted to Singapore for re-sentencing; Yasin received two years' imprisonment for this reduced charge in May 1976. He was subsequently retried for rape in 1977; the High Court convicted him of attempted rape rather than rape, citing insufficient certainty that intercourse occurred while Poon was alive, and sentenced him to eight years' imprisonment, to run consecutively with his other sentence.
Yasin was released in 1983 after serving approximately ten years in total. Harun was released in 1985 after completing his 12-year sentence. The Privy Council's ruling in this case, Mohamed Yasin bin Hussin v Public Prosecutor, became a significant precedent in Singaporean criminal law regarding the interpretation of Section 300(c) of the Penal Code, which concerns the definition of murder in cases without direct intent to kill, and continues to be studied in Singaporean law curricula.
16 dated entries · 1972–1994
Poon Sai Im is robbed and fatally assaulted on Pulau Ubin by Mohamed Yasin bin Hussin and Harun bin Ripin; her body is thrown into the sea.
Poon's daughter finds her missing and the family reports it to police.
A fisherman recovers Poon's body from the sea; it is identified by police.
Harun bin Ripin is arrested on an unrelated matter and confesses to his role in the robbery, implicating Yasin.
Yasin is arrested and both men are charged with murder.
Trial of Yasin and Harun begins in the High Court.
Yasin is convicted of murder and sentenced to death; Harun is convicted of robbery by night and sentenced to 12 years' imprisonment and caning.
Court of Appeal dismisses Yasin's appeal against his murder conviction and death sentence.
Privy Council hears Yasin's appeal.
Privy Council allows Yasin's appeal, overturning the murder conviction and death sentence, substituting a conviction under Section 304A of the Penal Code.
Yasin is sentenced to two years' imprisonment for the reduced charge.
Yasin's retrial for rape begins in the High Court.
Yasin is convicted of attempted rape and sentenced to eight years' imprisonment, to run consecutively with his other sentence.
Yasin is released from prison after serving a total of approximately ten years.
Harun bin Ripin is released after completing his 12-year sentence.
Singapore abolishes the avenue of appeal to the Privy Council.
3 named in this file
Victims first. Every legal label is set from public records and court outcomes, not from the prose.
58-year-old provisions shop owner on Pulau Ubin, robbed and killed on 22 April 1972.[3]
Convicted of robbery by night; sentenced to 12 years' imprisonment and 12 strokes of the cane.[3]
Initially convicted of murder and sentenced to death; conviction overturned on appeal to the Privy Council, which substituted a conviction under Section 304A of the Penal Code (causing death by a rash or negligent act); later convicted of attempted rape upon retrial.[3]
From the record
3 cited
Coverage is not a source: every fact in this file rests on the records below.
PressBAILIIAccessed Jul 7, 2026
Presseresources.nlb.gov.sgAccessed Jul 7, 2026
EncyclopedicWikipediaAccessed Jul 7, 2026
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