The police in Dublin said the cause was not known. An autopsy was scheduled.
Ms. Price, the former wife of the Irish actor Stephen Rea, attracted more public attention than she might have expected in recent years. Since 2011, the police in Northern Ireland police have been fighting in the courts for access to audiotaped interviews that Ms. Price gave to an oral history project at Boston College in which she detailed her I.R.A. career. The United States Supreme Court has been asked to hear the case.
The police learned of the audiotapes from an interview Ms. Price gave to an Irish newspaper in 2010. She told the paper that her testimony for the college’s “Belfast Project” described kidnappings and executions that she said she helped carry out in 1972 on orders from Mr. Adams. She also asserted on the tapes, she said, that Mr. Adams had a role in conceiving the London car bombings and that he ordered her and nine other I.R.A. volunteers, including her sister Marian, to carry them out in 1973.
The explosions, at four landmark sites, including the Old Bailey Courthouse, injured 200 people and left one man dead from a heart attack. It was the I.R.A.’s first attack in London.
Mr. Adams, who has intermittently been a member of the power-sharing Northern Ireland Assembly since a peace agreement was forged in 1998, has repeatedly denied her accusations. On Thursday he said he had “no concerns, because they are not true.”
The Northern Ireland police have said that Mr. Adams is not a target in their seeking the audiotapes. The family of one suspected I.R.A. informer described by Ms. Price as having been executed has called for Mr. Adams’s arrest.
Mr. Adams expressed sorrow this week at the news of Ms. Price’s death.
"She endured great hardship during her time in prison in the 1970s,” he said.
Ms. Price spoke often of the personal toll of her terrorist activities: years of depression, alcohol and drug abuse, and post-traumatic stress disorder. Among the suspected informers she drove to their executions, she said, was a longtime family friend. In prison, she staged a 203-day hunger strike in which her jailers force-fed her every day through rubber tubing.
Suffering from tuberculosis and other ailments, Ms. Price was released from prison on humanitarian grounds in 1981 after serving seven years of a life sentence.
Ms. Price told interviewers that she might have spared herself and her victims had she known that the struggle would end with a peace that left Northern Ireland’s Catholic majority, in her view, where it had started: under British rule.
“When we starved together on hunger strike,” she wrote in a 2004 essay in Fortnight, an Irish journal, “it was not to ‘move the process forward,’ it was not for seats in a British government.” It was, she said, “to rid this land of any British interference.”
Ms. Price married Mr. Rea in 1983 and had two children with him. Mr. Rea, who portrayed an I.R.A. hit man in the 1992 film “The Crying Game,” spoke only obliquely about his wife’s past.
“You can’t be born in the north of Ireland and not be political,” he told the British newspaper The Evening Standard in 1992. “The situation there is a pollution of your thinking.”
Dolours Price was born in Belfast on June 21, 1951, into a family steeped in Irish republican politics. Her father, Albert, was an I.R.A. founding member. “My father never saw his firstborn child because she was born and died while he was interned,” she wrote.
An aunt, Bridie Price, lost both hands and her eyesight when a bomb she was assembling accidentally blew up. Her sister Marian, who was among the 10 I.R.A. members involved in the 1973 London bombings, was released from prison in the early ’80s but rearrested several years ago on charges of plotting an attack on the government.
Ms. Price was a recent college graduate and training to be a teacher when she enlisted in the I.R.A. in the early 197os. She was one of the first women assigned to carry out an armed attack and was selected for the London mission in part, she said in an interview, because she was a pretty young woman and had no arrest record.
Ms. Price’s marriage to Mr. Rea ended in divorce in 2003. She is survived by their children, Danny and Oscar; her sister Marian and another sister, Clare; and two brothers, Sean and Dino.
Ms. Price remained defiant to the end. She had no truck, she said, with those whose political views had changed over the years. “I am a republican, born and bred, as were my mother and father before me and theirs before them,” she wrote in a letter to an Irish newspaper last year. “I have no time for people who constantly change their position.”
“They are not republicans,” she wrote.
Douglas Dalby contributed reporting from Dublin.
