A former IRA man behind controversial claims about Sinn Fein's Martin McGuinness on Bloody Sunday has begun giving evidence at the Saville Tribunal.
The inquiry is examining the events of 30 January 1972
Paddy Ward is addressing the inquiry from behind screens on Monday, and is expected to be in the witness box for two days.
The inquiry is examining the events of 30 January 1972 when 13 civilians were shot dead by soldiers during a civil rights march in Londonderry. Another man died later from his injuries.
Mr Ward accused the IRA of trying to discredit him, and claimed that people had been pulled into line to make accusations against him.
Mr Ward is to be questioned about his claims that Mr McGuinness and another IRA man gave him detonators for 16 nailbombs for a planned attack near the Guildhall in Londonderry on Bloody Sunday which was subsequently called off.
Mr McGuinness has rejected Mr Ward's claims in a second statement to the tribunal.
Mr Ward has also claimed that he was the leader of the Fianna, the junior wing of the IRA in Derry.
Sinn Fein councillor Gerry O'Hara contradicted Mr Ward's account
However, a Sinn Fein councillor in Derry has made a statement to the inquiry in which he says that he was the leader of the Fianna, directly challenging Mr Ward's claims.
Gerry O'Hara is to tell the inquiry that he was given an order there would be no action against the security forces and that the order was followed.
Mr O'Hara says Mr Ward's claims that he distributed 16 nailbombs on Bloody Sunday with the help of Mr McGuinness were simply untrue and that the Fianna had no access to weapons or explosives.
Meanwhile, another two former IRA members have also come forward to give evidence to the tribunal.
Both men will say that orders not to attack the security forces on Bloody Sunday were followed.
Lord Saville of Newdigate and the Commonwealth judges accompanying him on the Bloody Sunday inquiry began their work nearly four years ago.
They are not expected to report back until next year.
The Bloody Sunday Inquiry was established in 1998 by Prime Minister Tony Blair after a campaign by families of those killed and injured.
They felt that the Widgery Inquiry, held shortly after the shootings, did not find out the truth about what happened on Bloody Sunday.