They brazenly robbed the traders in broad daylight and made off with cash totalling $1,274,191.
The five men committed the offence at a two-storey Dunlop Street lodging house in Little India at around 8.30am on Sept 10, 2012.
After a 29-day trial, the court yesterday found four of them guilty of three counts of gang robbery each.
Two of them are Singaporeans - musician Magesan Ramasamy, 36, and Mohamed Faizal Ajmalhan, 32, who worked in the financial industry.
The other two are Indian nationals Arunachalam Lakshmanan, 37, and Chinnaya Antony Samy, 38. Both were construction workers.
The court also found Mohamed Faizal and Magesan guilty of three counts of impersonating police officers to rob their victims. The fifth man, Singaporean taxi driver Mohammad Ansari Abdul Hussain, 36, was earlier sentenced to eight years' jail and ordered to receive 12 strokes of the cane.
In their submissions, the prosecution said that according to Arunachalam and Chinnaya, their victims - Indian nationals Antony Savarimuthu, Gulam Hussain Jalaludeen and Abuasanar Kamarulzaman - were carrying out an illegal money remittance business in 2012.
The gang then decided to rob them.
On Sept 10 that year, the three Singaporeans wore police uniforms provided by Mohammad Ansari, a police NSman, and confronted the traders in the lodging house.
They used plastic flexicuffs to restrain their victims before helping themselves to the money. Meanwhile, their two accomplices acted as lookouts nearby.
The trio escaped in a car with stolen number plates to a multi-storey carpark in Upper Boon Keng Road. They then went to Mohammad Ansari's flat and divided the loot.
Before giving his verdict yesterday, District Judge Low Wee Ping said the case "could have started as a ruse" that "developed into a robbery".
He also said that one of the male victims cried in the stand when he was giving his testimony and this was something the court "seldom sees".
Judge Low said the ordeal had shaken this victim and felt that he could have suffered from "post traumatic syndrome".
The case is adjourned to June 16.
This article was first published on June 6, 2015.
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