Toxicology tests are likely to be carried out on the body of convicted IRA bomber Dolours Price, who was found dead at her home in Malahide, Co Dublin.
They will follow a post mortem due to be held today and the results will be included in a report prepared by gardai for a coroner's inquest.
The 61-year-old mother of two sons died at her home at St Margaret's Road on Wednesday night.
Gardai said they were investigating what they described as a sudden death. It is understood that she had recently been discharged from hospital after treatment for an illness.
Sinn Fein president Gerry Adams expressed his sadness at her death but refused to comment on her allegations concerning the role that Ms Price said he played in the Provisional IRA in the past.
Ms Price had been engulfed in controversy in recent months after giving a number of interviews in which she claimed that she had driven Belfast mother-of-ten Jean McConville to her death at the hands of the IRA.
She alleged that Mr Adams had ordered the murder but he has consistently denied the accusation.
Ms Price made the allegations to researchers working for Boston College in the US and the PSNI has since been seeking the tapes as potential evidence.
The two researchers, journalist Ed Moloney and Anthony McIntyre, said last night that the interviews would not be immediately handed over.
They said the tapes were the subject of a stay imposed by the US Supreme Court and that this remained in place until the court decided otherwise.
Mr Adams said Ms Price's death was "very, very sad" and that she had had a difficult life. He added that her passing would be a huge blow for her family, particularly her two sons, Danny and Oscar.
Mr Adams and Sinn Fein have repeatedly rejected her allegations about his IRA past and the party described her as an "opponent of the peace process".
The Sinn Fein president refused to comment on his party's past statements about her and said it was "not the time" to discuss those matters.
Ms Price and her sister Marian were members of a 10-strong Provisional IRA unit that planted four car bombs in London, including one close to the Old Bailey, in March 1973.
The 10, including Gerry Kelly, now a Sinn Fein minister in the Assembly, were arrested at Heathrow airport as they were boarding a plane to return to Belfast.
The two sisters were sentenced to life and started a 200-day hunger strike, which was called off in 1974, as part of a campaign to be repatriated to Northern Ireland. They were transferred to prisons in Northern Ireland the following year.
Following her release on compassionate grounds in 1980, Dolours Price moved to Dublin and married actor Stephen Rea. They divorced in 2000.
She became an opponent of the peace process and was critical of Sinn Fein while aligning herself with dissidents.
Marian Price had her release from prison on licence revoked in 2011. She is now in custody in a hospital in Northern Ireland.