New questions have emerged over the secret deal between Tony Blair and Sinn Fein to send so-called "comfort letters" to IRA fugitives, after two suspects in a terrorist massacre were told they were not wanted by police.
Police have discovered that the two individuals, who have not been publicly named, were linked to the 1976 Kingsmills Massacre in which 10 Protestant textile workers returning home were shot dead.
Under a scheme run by the Blair government, the two suspects were told they would not face questioning if they returned to the UK. One is now believed to be dead. An inquest into the massacre is due to open later this year.
The disclosure emerged in a letter obtained by British MPs investigating the operation of the "comfort letters" scheme, which Mr Blair developed in an attempt to satisfy Sinn Fein and keep Republicans from walking away from the peace process.
The existence of the letters, written by the British government and sent to 200 individuals via Sinn Fein, emerged a year ago when the trial of the alleged Hyde Park bomber, John Downey, collapsed.
Mr Downey denied killing four soldiers in the 1982 attack and his trial folded when his lawyers produced a letter from the Northern Ireland Office stating that he was no longer wanted by police. The case prompted a public outcry.
This week, Mark Sweeney, the British civil servant who wrote the "comfort letter" to Mr Downey, will be questioned by MPs in London investigating what has been described as his "catastrophic mistake".
Little is known about who else received letters, but details seen by UK newspapers disclose that two Kingsmills suspects were among them.