For nearly three decades, the Iranian authorities have systematically concealed the whereabouts of thousands of political prisoners, including prisoners of conscience, who were forcibly disappeared and extrajudicially executed in 1988. Amnesty International and Justice for Iran have documented how the authorities have destroyed or damaged mass grave sites across Iran that are believed to contain the remains of the victims. Amnesty International and Justice for Iran call on the authorities to stop the destruction of mass grave sites and ensure that they are preserved until proper, independent investigations can be carried out.