Then Prime Minister Lee Kuan Yew called off a visit to Pasir Panjang constituency on Nov 28, 1965, as a key man in an Indonesian arms conspiracy was still missing and constituted a security risk.
Mr Lee, who appeared at the third anniversary celebrations of the Kampung Tengah Community Centre in Sembawang on the same day, said he had been advised to cancel the visit. "I was persuaded not to test my good fortune."
He added: "Five years ago, I moved freely, first, because nobody was organised to get rid of anyone of us, let alone me; second, in any case, it wasn't worth getting rid of people."
"But today in independent Singapore, it is a very different situation. If people do get bumped off, then a great deal of uncertainty may follow."
The key man in question was Shafie Haji Ali, 38, a former member of the socialist Party Rakyat, who was trained in Indonesia. The missing man was initially wrongly identified as Johari Sonto, who was then serving a jail term in Malaysia for the possession of arms.
Nine of Shafie's associates were arrested a week earlier by the police, who had received information about a group that called itself the Tentera Nasional Republik Malaya (National Army of the Republic of Malaya) and operated in the Pasir Panjang, Ulu Pandan and Coronation Road areas.
A number of people from the group had been trained in Indonesia and a certain amount of arms, ammunition and explosives were recovered from them, said a statement from the Prime Minister's Office (PMO).
The group was believed to have received the weapons from Indonesia.
The PMO added that the Ministry of Defence was not satisfied that the arms recovered accounted for all the weapons that the group was given and concluded that there was a security risk.
According to the police, Shafie was the last of 19 Party Rakyat members who left Singapore in 1963 for training in sabotage and espionage in Brastagi, Sumatra.
Early in 1964, he landed in the south of Malaya and was known to be in Singapore in October 1965.
But Dr Mohamed Abu Bakar, chairman of Party Rakyat, accused the ruling People's Action Party of trying to smear the name of his party.
"The party cannot be blamed for the personal activities of its members," he said.
This article was first published on November 29, 2015.
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