SINGAPORE - The Singapore Government has rebutted recent allegations by former political detainees and some historians that a major crackdown on leftists in 1963 was a political exercise, saying the claim was "misleading and disingenuous".

A full reading of the available evidence would highlight the "serious security threat" the Communists posed, it said.

The crackdown, Operation Coldstore, was a continuation of security operations mounted since 1948 to contain the Communist Party of Malaya (CPM).

The fact that the operation shattered the CPM's underground network throughout the island was acknowledged by no less than CPM secretary-general Chin Peng in his memoirs, it said.

"Clearly Operation Coldstore had not targeted innocent, non-communist 'socialists'."

The Government's comments were made by Singapore High Commissioner to Australia Burhan Gafoor in a strongly-worded letter on Thursday to the Australian National University's New Mandala website.

They were in response to a commentary on the website by former Coldstore detainee Poh Soo Kai earlier this month.

Dr Poh, a former Barisan Sosialis leader, was among 113 left-wing politicians and unionists rounded up in Coldstore, which he called a "set-up" against political opponents of then prime minister Lee Kuan Yew, including Barisan chief Lim Chin Siong.

The Straits Times at the time reported that the arrests of these members of communist united front (CUF) groups were aimed at preventing subversives from setting up a "communist Cuba" in Singapore and mounting violence as Malaysia was to be formed.

Dr Poh's commentary follows the bid by some historians in recent years to shed new light on Singapore's political developments in the 1960s, basing their work on confidential and secret records of the British colonial authorities that were declassified in the past 10 years.

Several academics and officials have rebutted the revisionists' claims, and in October this year, the Government reissued The Battle For Merger radio talks that then PM Lee gave in 1961 to expose the Communist agenda.

A marker to commemorate some 8,000 victims of Communist violence in Malaysia and Singapore from 1948 to 1989 was also unveiled at Esplanade Park last Monday.

Dr Poh criticised the radio talks reprint, describing it as a "Cold War diatribe" and aimed "implicitly to justify Coldstore".

Mr Burhan's letter is the first official response to cite the declassified documents from the British archives. It also reiterates what former CPM leaders had said about Barisan Sosialis, the CPM network in Singapore and Mr Lim Chin Siong.

Mr Burhan noted that "revisionists" like Singaporean historian Thum Ping Tjin "conveniently omit mention" of incriminating information in the declassified documents, like the colonial officials' concern about the extent the CPM had penetrated the Barisan.

"The Barisan was not an ordinary left-wing political party, and its leaders were not 'unwitting dupes' of the Communists. It was the prime CUF body in Singapore in the 1960s, influenced, directed and led by CPM cadres," he said.

In his nine-page letter, Mr Burhan outlined how the evidence showed "they were ready, when the opportunity arose, to use violent unconstitutional means to overthrow the Government".

He said the British Commissioner to Singapore, Lord Selkirk, had by late 1962 recognised the extensive Communist hold on the party and said "it would be wise to make arrests of communists in Singapore as soon as possible''.

Mr Burhan also said there was "ample evidence" in the British archives, and accounts by CPM members, to show that Lim Chin Siong played a key role to advance the CPM's cause.

"What is missing is an explanation from the revisionists as to why they have systematically ignored revelations by CPM leaders, as well as the many British documents that demolish their claims," he said.

Dr Poh had also failed to explain his role in helping CPM elements between 1974 and 1976, he added, saying: "A mere 'left wing' anti-colonialist, as Dr Poh describes himself now, would not have given material aid surreptitiously to the CPM's violent armed struggle as late as 1976."

He also said Dr Poh and the revisionists' disregard of the facts "is disrespectful to the many Singaporeans who chose a non-communist path at great risk to themselves, and contributed to the success of modern Singapore".