The killings have been described as a political purge without precedent in modern Iranian history, both in terms of scope and coverup. However, the exact number of prisoners executed remains a point of contention. Amnesty International, after interviewing dozens of relatives, puts the number in thousands; and then-Supreme Leader Ruhollah Khomeini’s deputy, Hussein-Ali Montazeri put the number between 2,800 and 3,800 in his memoirs, but an alternative estimation suggests that the number exceeded 30,000. Because of the large number, prisoners were loaded into forklift trucks in groups of six and hanged from cranes in half-hour intervals