A SINN Fein TD is believed to have been involved in 50 murders during the Troubles, new documents reveal.
Secret internal communications within the British government suggest that Dessie Ellis, then a member of the IRA, was forensically linked to the deaths in the Republic and in Northern Ireland.
And another communication dealing with Mr Ellis refers to him as a "leading PIRA" (Provisional IRA) member.
Mr Ellis, who is now the Sinn Fein TD for Dublin North-West, was sentenced to 10 years in prison on explosives charges in the 1980s.
He declined to comment on the newly released papers from 1982. "No, I won't be saying anything," Mr Ellis told the Irish Independent.
When asked if he disputed the claims, he said: "I don't want to comment on anything said by the Brits. I wouldn't be bothered."
The detail will be hugely embarrassing for Sinn Fein, which has come under severe criticism recently because of its links to the IRA.
The Government, in particular, has consistently tried to remind voters of Sinn Fein's past, with the Taoiseach Enda Kenny and Tanaiste Eamon Gilmore launching stinging attacks.
On the last day that the Dail sat before Christmas, Mr Gilmore asked Sinn Fein's Mary-Lou McDonald: "How many bodies are buried on this island because of Sinn Fein?"
Mr Ellis (60) has refused to detail his position in the IRA during the Troubles, except to say that he was "at the highest levels".
In a recent book about his home area, Finglas in Dublin, Mr Ellis said he became involved in republicanism from an early age – first in the civil rights marches and later in the "armed struggle".
He was elected a TD in 2011 on his third attempt.
Mr Ellis, a former TV-repair man, was initially arrested in Dublin in May 1981 but jumped bail and fled to Canada, from where he crossed the border into the United States. He was arrested in Buffalo, New York, in 1982 on immigration offences.
An internal communication marked "secret" from the British embassy in Washington states: "As you know, one of those arrested has turned out on investigation to be Desmond Ellis, who was arrested in Dublin in May 1981 for possession of electronic remote-controlled devices.
"We understand that Ellis is linked by forensic evidence to some 50 murders in Northern Ireland and the Republic."
The document is one of a large tranche of British government files from 1982 that have been released by the National Archives in London.
The 1982 communication states that Mr Ellis was wanted in Dublin. It adds that, given his record, "we hoped that steps could be made to ensure that he was not simply sent back to Canada following next Tuesday's (immigration) court hearing and escape from justice."
It further adds that the authorities here wanted him returned to Ireland, but that it would be difficult to hold him in the US in the absence of an extradition agreement.
Mr Ellis was later extradited to Ireland and in 1983 he was convicted by the Special Criminal Court. He was sentenced to 10 years' imprisonment.
Later, in 1990, he was the first person charged under the 1987 Extradition Act for an explosives charge in England.
He then went on a hunger strike that lasted 37 days in protest against his pending extradition to England. He was eventually acquitted in London.
The new revelations come after Sinn Fein has come under intense pressure in the Dail over its links to the IRA.
The Dail was suspended earlier this month after a furious row erupted between Mr Kenny and Sinn Fein leader Gerry Adams over the disappearance of Jean McConville.
Mr Kenny said it was time that Mr Adams told the truth about his past, specifically mentioning the mother of 10, who was murdered by the IRA.
The following day, the Dail was again suspended for 45 minutes when Sinn Fein TD Padraig Mac Lochlainn objected to the Taoiseach's remarks.
SINN FEIN TD Dessie Ellis did not want to discuss the release of British state papers which said he was believed to have been involved in some 50 murders during the Troubles. The following is a transcript of what he said when Irish Independent reporter Cormac McQuinn called to his home.