Cathal Mcnaughton / Reuters

A woman walks past a mural to murdered lawyer Pat Finucane on the Fall's Road in West Belfast on Wednesday.

LONDON -- British Prime Minister David Cameron said on Wednesday there had been "shocking" levels of state collusion in the murder of Belfast solicitor Pat Finucane in 1989.

Cameron was quoting from a new report into the killing of Finucane by British lawyer Sir Desmond de Silva, saying that while it did not find that there had been an "over-arching state conspiracy" over the murder, it was still "extremely difficult reading."

Finucane, a Catholic whose clients included members of the anti-British Irish Republican Army (IRA) guerrilla group, was shot dead by pro-British paramilitaries in front of his wife and their three children as they sat down to dinner.

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There have since been long-running allegations of state collusion in the murder, one of the most controversial in 30 years of sectarian conflict in Northern Ireland.

Speaking in parliament, Cameron said of the report: "It sets out the extent of collusion in areas such as identifying, targeting and murdering Mr. Finucane, supplying a weapon and facilitating its later disappearance and deliberately obstructing subsequent investigations."

He repeated a British government apology to Finucane's relatives but said he would not order a full public inquiry, as the family have been demanding.

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Finucane's widow, Geraldine, said the report was "a sham... a whitewash... confidence trick," ITV News reported.

Meanwhile, Labour leader Ed Miliband called for a full public inquiry into the murder and said the De Silva report had its limits.

Reuters and ITV News, NBC News' U.K. partner, contributed to this report.

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