Sinn Féin President Gerry Adams has launched a legal bid to overturn two historical convictions for attempting to escape from prison in the North.
Mr Adams confirmed that he had started appeal proceedings in Belfast over incidents which occurred while he was interned without trial in the Maze Prison in the 1970s.
The Sinn Féin leader said he is appealing against convictions he received in 1975 in two separate Diplock Court trials - cases tried by a judge sitting without a jury - relating to two attempts to escape from internment.
"Following the recovery of a document by the Pat Finucane Centre in October 2009 from the British National Archives in London, I instructed my solicitor to begin proceedings to seek leave to appeal the 1975 convictions," he added.
Mr Adams was among hundreds of republicans held without trial during the height of the Troubles in the North.
He has lodged papers with the Court of Appeal, with a hearing is due to take place in the Autumn.
The Northern Ireland Court Service confirmed: "Gerard Adams is appealing against two convictions for attempting to escape from detention in the 1970s."
Internment without trial for those suspected of being involved in violence was introduced in 1971 by Northern Ireland Prime Minister Brian Faulkner.
Mr Adams was interned in March 1972, but was released in June that year to take part in secret talks in London.
He was rearrested in July 1973 at a Belfast house and interned at the Maze Prison, also known as Long Kesh internment camp.
On Christmas Eve 1973, he was one of three prisoners apprehended by warders while trying to cut their way through the perimeter fencing.
In July 1974, according to British Government files, he again attempted to escape by switching with a visitor at the Maze.
He was subsequently sentenced to 18 months' imprisonment for attempting to escape.
While in prison, Mr Adams wrote articles for republican newspaper An Phoblacht under the pen name Brownie.
In the first wave of internment raids across Northern Ireland, 342 people were arrested.
The policy of internment lasted until December 1975. During that time, 1,981 people were held - 1,874 nationalists and 107 loyalists.
The introduction of internment, the way the arrests were carried out and the abuse of those arrested led to mass protests and a sharp increase in violence.