The convicted IRA bomber, Dolours Price, has been found dead at her home in County Dublin.
Her family have confirmed that she died in Malahide on Wednesday night and they are to release a statement later.
The 62-year-old was jailed for her part in an IRA bomb attack on the Old Bailey in London in 1973, that injured 200.
In recent years she had aligned herself with dissident republicans and was an outspoken critic of the IRA leadership and Sinn Fein President Gerry Adams.
In media interviews before she died she alleged that during her time in the IRA, Mr Adams had been her commanding officer.
She also claimed that she drove Belfast mother-of-10 Jean McConville to the place where she was murdered by the IRA in 1972.
Dolours Price was born in 1951 and was originally from Belfast. In 1973 she was convicted as part of the IRA unit that carried out the Old Bailey bombing, along with her sister Marian Price and the Sinn Fein MLA, Gerry Kelly.
More than 200 people were injured and a man, who suffered a heart attack when the bomb exploded, subsequently died.
The Price sisters were given life sentences and went on hunger strike, demanding to be allowed to serve their jail term in Ireland.
After her release on compassionate grounds in 1980, Dolours Price married the actor Stephen Rea. The couple have two sons but divorced in 2000.
She was also the catalyst for a transatlantic legal battle over secret testimony she gave to an American college about her time in the IRA.
Over a decade ago, she was one of 26 former IRA members to give a series of interviews to Boston College, as part of its oral history research project into the Troubles in Northern Ireland.
Recordings were carried out with both loyalist and republican paramilitaries, on the understanding that they would be made public only once interviewees had died.
Jean McConville, a mother of 10 from Belfast, was abducted and murdered by the IRA in 1972
In 2011, the Police Service of Northern Ireland (PSNI) launched a legal bid to force the college to hand over the transcripts, as part of their investigation into the murder of Jean McConville.
The 37-year-old mother was abducted from her Belfast home and shot in the head in 1972.
Mrs McConville was one of the so-called Disappeared, people who were murdered and secretly buried by the IRA.
Her body was found more than 30 years later on a beach in County Louth.
In media interviews, Dolours Price claimed to have been the person who drove Mrs McConville to her death.
The researchers at Boston College fought the PSNI action, arguing that surrendering the transcripts would put lives at risk and compromise future oral history projects as a confidentiality agreement had been broken.
The BBC's Ireland correspondent Andy Martin said that those close to Boston College's Belfast Project say that the death of Dolours Price means that her recorded interviews will now simply be handed over as a matter of course.
"The agreement the university made with the interviewees was that their testimony would be kept secret, and securely in the Burns Library on its main campus, until after the contributors had died," the correspondent said.
Gerry Adams has rejected allegations made by Dolours Price about his involvement in the IRA
"This was the case with prominent IRA commander Brendan Hughes, whose revelations about his role during the Troubles were later published in a book and formed the basis of a television documentary, along with those of the former UVF member and later leader of the Progressive Unionist Party, David Ervine."
However, he added that project director, Ed Moloney, has already countered some newspaper claims that Dolours Price made any comment about the involvement of Gerry Adams in the deaths of the Disappeared, something which the Sinn Fein leader has always denied.
It is not yet known how Dolours Price died but police in Dublin have confirmed they are investigating the death of a woman at a house in St Margaret's Road in Malahide.
BBC News - Ex-IRA woman Dolours Price is found dead in Dublin