Police are investigating two separate murder cases, believed to involve the suspects' loved ones.
The police were alerted to the first death in Ang Mo Kio Avenue 6 at dawn, and a 63-year-old man was found lying motionless.
He was pronounced dead by paramedics at the scene. A 54-year-old woman is set to be charged in court today. Neighbours said they regularly saw the couple together.
After dusk, the police were alerted to two unnatural deaths in Commonwealth Avenue. Two women, aged 56 and 90, were found lying motionless and pronounced dead at the scene. Two other persons were taken to the National University Hospital by ambulance.
A 22-year-old man is set to be charged in court today. Preliminary investigations showed the deceased and the suspect were related.
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