Countering Threats

Over the years, ISD and its predecessor, Special Branch, have dealt with many threats to Singapore’s internal stability, security and sovereignty:



The communists posed a big threat to Singapore’s stability and security from the late 1940s to the 1980s. In 1948, the Communist Party of Malaya (CPM) launched an armed struggle against the British in Malaya and a state of “Emergency” was declared. The Special Branch carried out several successive operations against the communists in the 1950s and 1960s and managed to cripple the CPM’s united front networks among the trade unions, Chinese middle schools and other mass organisations which the CPM had exploited to organise strikes and other forms of political agitation. The CPM terrorist squads carried out assassinations or assassination attempts on Special Branch and Police officers, both in Malaya and Singapore.

Singapore continued to face the communist threat after Independence in 1965. Pro-communist elements resorted to “extra-parliamentary” struggle through organised strikes and acts of arson and vandalism. The CPM revived its underground networks to carry out assassinations and “bombing” assignments. The ISD intensified its efforts against the CPM and by late 1970s had eradicated almost the entire communist underground network in Singapore. The CPM threat declined with the CPM signing peace pacts with both the Malaysian and Thai authorities in 1989 to lay down their arms.


Communal Challenge

The first serious racial riots which the Special Branch had to deal with soon after its formation in 1948 was the Maria Hertogh riots of 1950 where Muslim rioters attacked Europeans, Eurasians and Christians. A total of 18 people were killed and 173 injured.

When Singapore was in Malaysia, we experienced serious Sino-Malay riots in 1964, instigated by outside forces. Over 500 people were injured and 36 lives were lost in the clashes between Chinese and Malays. The ISD, together with the Police, helped contain a volatile situation. Sino-Malay tensions surfaced again in Singapore in 1969 following the outbreak of the 1969 racial riots in Malaysia after the General Election. Many incidents of Sino-Malay clashes erupted and the situation was brought under control following security sweeps by the Police and armed forces throughout Singapore. The vigilance of the security forces in Singapore and the persistent efforts of ISD officers in making island-wide coverage contributed to the return of normalcy in Singapore.

burnt car

1964 Racial Riots

racial riot

1964 Racial Riot

While Singapore has not seen racial riots since then, there have been cases of racial and religious extremists who attempted to disrupt racial harmony and stability. In 1982, the ISD exposed a clandestine subversive Muslim group known as the Singapore People’s Liberation Organisation (SPLO) which planned to cause communal unrest in Singapore by exploiting religious and racial issues. The objective of the group was to overthrow the Government by violent means. They planned to create communal unrest by distributing subversive pamphlets and carrying out acts of arson or planting bombs at public places. Then in Apr 1987, four silat (martial arts) exponents were arrested by the ISD for actively spreading rumours of impending racial clashes on or around 13 May 1987 (on the 18th anniversary of the May 1969 race riots in Singapore and Malaysia).

Above: Business Times 4th June 1987

Above: Items Belonging to the Silat Exponents Arrested in April 1987


Above: Weapons Seized from the Silat Exponents in April 1987


Singapore experienced its first terrorist incident on 31 Jan 74, when terrorists from the Japanese Red Army (JRA) bombed petroleum tanks at Pulau Bukom. During their escape from Pulau Bukom, the terrorists hijacked a ferry boat, “Laju” and took some crew member as hostages. The JRA terrorists demanded the release of their jailed comrades in other countries. The ordeal ended with several ISD and government officers volunteering as “hostages” in exchange for the release of civilian hostages. Among the Singapore officials was the then Director of Security & Intelligence Division, Mr S R Nathan. Singapore faced another terrorist incident in 1991 when four Pakistanis hijacked a Singapore Airlines shuttle flight SQ 117 from Subang International Airport (Kuala Lumpur) with 129 passengers onboard. The ISD played a significant role in collecting tactical intelligence crucial to the successful storming of the aircraft by SAF commandos.

The ISD is also involved in neutralising several attempts by terrorist groups using Singapore to raise funds or to procure electronic parts in aid of their struggle. In 1985, the ISD took actions to neutralise a local network of the Liberation Tiger of Tamil Ealam (LTTE) headed by Sri Lankans working in Singapore. Key leaders and activists of the network were arrested and expelled to countries of their choice. In Nov 2000, the ISD carried out a security operation against another local network of the LTTE whose principal activities were the secret collection and transfer of funds. These operations served to put these individuals on notice that the authorities will not tolerate their use of Singapore and Singapore citizens/permanent residents in activities which are prejudicial to Singapore’s security interests.

In Dec 2001, the ISD disrupted a terrorist cell here called the Jemaah Islamiyah (JI) which is part of a larger regional network with cells in Malaysia and Indonesia. The local JI members were planning to attack targets like Western embassies and personnel. Following leads from the first arrests, the ISD conducted another wave of arrests in Aug 2002 to detain more JI members. As a result, the local JI network was seriously disrupted.

Besides the 31 persons detained in the 2 major security operations, 7 other persons were arrested and detained between 5 Oct 2002 and 20 Dec 2003 in the on-going investigations (one of them was later released on Restriction Order). Another 12 Singaporeans, who have been assessed to be peripherally involved in terrorist activities, were served with Restriction Orders in Jan 2004. Ten of them were JI members and 2 others were members of the Moro Islamic Liberation Front (MILF) based in the Philippines. Thirty other persons were also warned to cease their links with terrorist groups.

The Advisory Board, an independent panel headed by a High Court judge, had reviewed the Orders of Detention (OD) of the JI members detained and upheld ISD’s recommendations. The Government has also published a White Paper on JI Arrests and The Threat of Terrorism.


While a terrorist incident is highly visible, espionage cases are not. In 1982, the ISD exposed and expelled two Russian spies for espionage activities in Singapore. One was Anatoly Alexeyevich Larkin, a Soviet military intelligence (GRU) officer, who attempted to cultivate an SAF army officer holding the rank of 2nd Lieutenant to conduct espionage against the SAF. The other was Alexander Alexandrovich Bondarev, another Soviet military intelligence officer, who was sent to take over a Soviet spy network which had a local agent working for it since the 1970s


More recent cases include the ones when the ISD arrested two persons in 1997 and another 4 persons in 1998 under the ISA for involvement in espionage and foreign subversive activities prejudicial to the security of Singapore. Of the two persons arrested in 1997, one was a male Singapore Permanent Resident who was a deep-cover operative of a foreign intelligence service. He had used the other, a female Singaporean, as a collaborator. Of the four Singapore citizens detained in 1998, three were controlled agents for a foreign intelligence agency. One of them recruited the fourth person to collect intelligence on and to subvert a local community organisation. All six of them have been released. 


Cyber intrusions against government, critical infrastructure and other information networks are substantial threats to Singapore’s national security and national interests.  These intrusions can also be conducted in support of larger subversion efforts. As such, ISD collects intelligence to counter these threats, in partnership with other stakeholders in Singapore’s national cyber security.  

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