The Heath government orchestrated a smear campaign in an attempt to falsely blame the IRA for an infamous Belfast bar bombing in 1971, a Labour MP told Parliament today.
Fifteen people died when a UVF bomb tore through McGurk's Bar in Belfast on December 4 1971.
Despite evidence to the contrary, the security forces initially blamed the atrocity on the accidental detonation of a republican device and suggested that IRA members who were carrying it may have been among the dead.
Then Stormont home affairs minister John Taylor said he believed the IRA was responsible.
In 1978 UVF member Robert Campbell was convicted for his part in the attack.
Last year the police Ombudsman said that there had been no collusion between security forces and loyalist paramilitaries but concluded that there had been investigative bias towards blaming republicans for the massacre.
Speaking in the Commons, Michael Connarty MP said that a new book by Ciaran MacAirt cast doubt on the findings of the ombudsman's report.
"There was collusion and it was clearly the British government, possibly up to the-then prime minister Edward Heath, who colluded and not only co-operated, but instructed that the false story be spread that this was a bomb carried by the people into that bar and it was an IRA bomb in transit," he said.
Mr Connarty urged Prime Minister David Cameron to apologise and order a full investigation.
"Is it not time now for a proper investigation by the British government into the facts of this case, with all the files being open and the Prime Minister coming here to apologise to those families and the community for the malign way in which they were, for six years, blamed for a bomb that was clearly a vicious act against them?"
Leader of the House Andrew Lansley said he would ask ministers to respond to Mr Connarty's claims.
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