On the afternoon of July 21, 1964, a large group of Chinese people hurled rocks and bottles at a procession of Muslims passing from the Padang to Lorong 12 Geylang to mark the birthday of Prophet Muhammad.
Among those leading the procession was Mr Othman Wok, who was to become a member of independent Singapore's first Cabinet about a year later.
Despite Mr Othman's best efforts, the provoked procession of Muslims turned violent too, triggering Singapore's worst racial riots, with 23 people dead, 454 injured and about 1,000 arrested.
Among those caught in the crosshairs that day was Raffles Institution schoolboy Ismail Ibrahim, the eldest brother of Dr Yaacob Ibrahim, Singapore's current Minister for Information and Communications and Minister-in-charge of Muslim Affairs as well as Cyber Security.
Dr Yaacob, 61, was eight years old at the time. In an interview with The Straits Times in September last year, he recalled how "worried sick" his family was. He said: "Ismail was caught in the whole thing on the way back and there was no telephone in our house."
Dr Yaacob's family was then living in a Changi kampung, where Somapah is today, and had many Chinese and Indian neighbours who were just as concerned about his brother's safety.
He added: "When Ismail finally came back, everybody, including the Chinese, was happy."
His late father, a law clerk, then formed a vigilante committee with the village headman and a few villagers to keep watch over all their neighbours in subsequent riots later that year. "It was a mixed team of Malays, Chinese and Indians. In fact, there was a Chinese village nearby, with gangsters and all, but they had a truce with us. They said, 'We protect one another; if an outsider comes, we go together and whack the outsider.'"
All that, he added, showed that the "seeds" of multi-culturalism had always been in Singapore.
He stressed, however, that these seeds were nurtured by the late founding prime minister Lee Kuan Yew and Mr Othman, and that they helped to "embed" multi-culturalism in Singaporean lives through, among other things, policies for Housing Board flats and the education system. Both men, Dr Yaacob noted, were convinced that "it was better for the Malays to be in Singapore than anywhere else", as the Government ensured that they had access to education and other channels for progress.
In Dr Yaacob's letter of condolence to Mr Othman's widow Lina Abdullah, 70, which was released yesterday, the minister said he found the late leader "sensitive and attentive" to the needs of Malay-Muslims here, to the extent that, with the help of Singapore's first attorney-general Ahmad Ibrahim, he successfully put in place a new system to order and administer their affairs. These ranged from registering their marriages and divorces to redistributing their wealth after death and administering madrasahs and mosques.
Besides attending Mr Othman's birthday celebrations in recent years, Dr Yaacob recalled meeting Mr Othman "several times" over a cup of coffee to discuss the challenge of preserving multi-culturalism in Singapore.
"He never came across as someone who kept insisting on his own way," said Dr Yaacob. "The one thing he kept on insisting is never to forget that multiracialism is important to us… and you can see it in the way he lived his life."
For instance, he stressed, the pioneer Cabinet minister never saw mosques as being different from anything else about Singapore.
"They had to be managed differently, professionally, and they had to deliver good services, which are Singaporean values that permeate everything in the Malay-Muslim community," Dr Yaacob said.
Today, thanks to Mr Othman's insistence on the highest standards in administering the Mosque Building Fund that he and Mr Lee implemented in May 1975, there are a total of 71 mosques in tiny Singapore.
Of these, 24 are new-generation ones, including the Yusof Ishak Mosque in Woodlands, named after Singapore's first President. The mosque was opened last Friday by Mr Yusof's widow, Puan Noor Aishah, in the presence of Prime Minister Lee Hsien Loong and Dr Yaacob.
It was an uphill task getting Singapore's Malay-Muslims to buy into even the idea of the fund. As Dr Yaacob put it: "It was no easy solution to force every Muslim worker to give 50 cents of the salary (to the fund)." In 1975, a packet of nasi lemak cost 30 cents.
Mr Othman's vision of multi-culturalism also lives on in the community's religious classes, said Dr Yaacob. "We teach them how to be good neighbours because your neighbour could be a Buddhist, Taoist and so on… You live side by side with non-Muslims and Muslims."
As Dr Yaacob noted in his condolence letter, Mr Othman was so "sensitive and attentive" to his community's needs that he "rolled up his sleeves" to clean neighbourhoods alongside them.
The move soon dispelled their distrust of him as a possible "traitor" to the community because he belonged to the People's Action Party, which they saw as pro-Chinese then.
Dr Yaacob's mother, who once lived in Kampung Ubi in Geylang Serai, saw her estate "transform" from a flood-prone area to one that is well landscaped.
He said: "Today, if you ask the elderly population including my mother, they say, 'We trusted him, that he would do the job.'"
Dr Yaacob believes the best way to preserve the multi-culturalism that Mr Othman so loved is to "build in our young a curiosity and appreciation of others" so that they do not think of themselves "as just a member of a race".
He added: "If you're not interested in knowing your neighbours, I think we're done for."