Malaysia's then-Prime Minister Tunku Abdul Rahman had initially rejected Lee Kuan Yew's proposal for a merger due to the fear of communist insurgency in Singapore and the large number of ethnic Chinese in Singapore which might outnumber the Malay population in Malaysia[4] (Additionally, Chinese Malaysians constituted a large portion of the population of Malaya/Malaysia at the time and continue to this day).

[5] However, Tunku changed his mind to call for the merger with Singapore, when the anti-communist Singaporean leader Ong Eng Guan was expelled from the People's Action Party (PAP) but still won a by-election as an independent.

[6] Furthermore, maintenance of the high number of Malays in Malaysia was addressed by the inclusion of Borneo island's regions Sabah and Sarawak into the Malaysian federation.

[12] With the breakdown of the truce, and in an attempt to portray itself as a Malaysian political party, the PAP fielded candidates in the Malay peninsula in the 1964 Federal elections on 25 April 1964.

[13] The PAP won one seat in Selangor, which was seen as an intrusion into Malaysia's political space and viewed by Tunku as a humiliating blow to the credibility of UMNO.

[12] Lee's intentions of creating a Malaysian Malaysia, advocating for equal treatment and opportunity for all races, was viewed with suspicion and hostility by UMNO.

The first riot occurred at the Padang when twenty-thousand majority Muslim Malays gathered for the procession to celebrate Mawlid, the birthday of the Islamic prophet Muhammad.

[17] Utusan Melayu's stated aim was to "fight for religion, race and its homeland", placing key emphasis on the rights and the elevated status of the local Malays in Singapore.

In that meeting, Lee assured the Malays that they would be given ample opportunities in education, employment, and skill training for them to compete effectively with the non-Malays in the country.

This meeting was chaired by Secretary-General of UMNO Syed Jaafar Albar who referred to Lee as an "Ikan Sepat" (three spot gourami), a mud-dwelling fish, and called for collective action against the Chinese community led by the PAP.

Accounts from the meetings[citation needed] indicate that the Malays in Singapore had no major grievances and that UMNO's Secretary-General Syed Jaafar was responsible for instigating them.

[6] From the Malaysian government's point of view, Lee Kuan Yew and PAP were responsible for instigating the riots and discontent among the Malay community in Singapore.

[23] On the other hand, PAP and Lee Kuan Yew strongly believed that the 1964 July riot was not a spontaneous one, as UNMO had always tried to stir anti-PAP sentiments and communal politics among the Singapore Malays.

On the afternoon of 21 July 1964, about 20,000 Malays representing the different Muslim organisations in Singapore had gathered for the procession to begin to mark the birthday celebrations of Muhammad.

But rather, part of the reasons could be also attributed to the distribution of leaflets to the Malay community before the start of the procession by a group named Pertobohan Perjuangan Kebangsaan Melayu Singapore.

Clashes and tensions between the Malays and Chinese re-arose, so the curfew was re-imposed at 11.30 a.m.[16] Political leaders of both Malaysia and Singapore, Tunku Abdul Rahman and Lee Kuan Yew, each led national radio broadcasts and emphasised the need to maintain peace and harmony among the different racial and religious groups.

This riot was triggered by the murder of a Malay trishaw rider along Geylang Serai and this incident sparked attempts of stabbings and heightened violence.

[26] Following the September riots, the Malaysian government finally agreed to form such a commission,[27] with closed-door hearings beginning in April 1965; however the findings of the report have remained confidential.

Furthermore, Tunku Abdul Rahman's encouragement of racial tension and anti-PAP sentiments among Singaporean Malays made it difficult for the PAP to work with UMNO to forge good relations.

[3] The July 1964 racial riots played a significant role in shaping some of Singapore's fundamental principles such as multiculturalism and multiracialism once it had gained independence from Malaysia in 1965.

[3] During this commemoration day, schools recall the racial riots that occurred, but the emphasis on the events are focused on the tension between the Malays and the Chinese rather than on the political and ideological differences between UMNO and PAP.