A Ministry of Defence (Mindef) defence executive assistant who was being detained at the Singapore Armed Forces (SAF) detention barracks suffered a cardiac arrest while taking a shower on Friday.
He died last night.
In a statement, Mindef said 54-year-old Sivaperumal Tanggayelu, who was detained on Oct 15 to "assist in investigations", had collapsed at about 6.49pm on Friday.
Mindef did not say what he was detained for.
A medic immediately tried to resuscitate Mr Sivaperumal, who was unconscious and without pulse.
He was then taken to the Tengah Air Base medical centre, where an SAF doctor assessed that Mr Sivaperumal had had a cardiac arrest.
Mr Sivaperumal was then taken to the National University Hospital's (NUH) emergency department at about 7.40pm, with resuscitation efforts continuing en route.
The administrative assistant was resuscitated at 8.15 pm but remained in critical condition, said Mindef. He died at 8.49pm on Monday.
Prior to his detention, Mr Sivaperumal had been assessed to be medically fit for remand and he had not reported sick or complained of feeling unwell when he started his detention, said Mindef.
He had also been excused from physical activities.
SAF is providing assistance to the family and investigating the incident.
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