Government classified files from 1980 released this week by the Public Record office in Belfast detail the attempt of the Sinn Fein president Gerry Adams to escape from prison in the 1970s.
The file, dealing with "Escapes and attempted escapes from custody" by republican and loyalist prisoners in the 1970s includes an incident report dated 26 July 1974 on Mr Adams.
The republican leader had been arrested the previous summer at a Belfast house and was being interned without trial.
An official recorded tersely that "Gerry Adams, detainee, attempted to escape by switching with his visitor" at the Maze Prison, near Lisburn.
The report, penned immediately after the event, noted that "both visitor and detainee are locked in the cells. Other female visitors are being held pending police inquiries."
For his escape attempt, Mr Adams was subsequently sentenced to 18 months' imprisonment.