An Iranian official accused of involvement in the of thousands of political dissidents goes on trial in on Tuesday in a landmark case likely to stoke tensions in the .
Hamid Noury, 60, is accused by Swedish prosecutors of "intentionally taking the life of a very large number of prisoners sympathetic to or belonging to the People's Mujahedin" (MEK) between 30 July and 16 August 1988, while he was assistant to the deputy governor of Gohardasht prison in Karaj, near Tehran.
Human rights organisations have long for justice for the estimated 5,000 prisoners killed across Iran, allegedly under the orders of supreme leader Ayatollah Khomeini in reprisal for attacks carried out by the MEK at the end of the Iran-Iraq war of 1980-88.
Swedish court officials believe Tuesday's case is the first of its kind against someone accused over the killings.
The allegations were brought to the attention of the Swedish authorities by a group of 30 complainants, as well as justice campaigner and former political prisoner Iraj Mesdaghi.
After compiling an evidence dossier of "several thousand pages" on Noury, Mesdaghi set about luring the former prison official to the Nordic country with the promise of a luxury cruise. Noury was arrested as he stepped onto Swedish soil.
Sweden's principle of universal jurisdiction means that its courts can try a person on serious charges such as murder or war crimes regardless of where the alleged offences took place.
"This is the first time that one of the persecutors has been held accountable in another country," Mesdaghi told AFP.
Noury "denies any accusation of involvement in the alleged executions of 1988," his lawyer Thomas Soderqvist told AFP.
The case is particularly sensitive in Iran, where campaigners accuse current government figures of having a role in the deaths, most notably new president Ebrahim Raisi.
The former head of Iran's judiciary was accused by Amnesty International in 2018 of being a member of a "death commission" which was behind the secret executions.
Questioned in 2018 and 2020, Raisi denied involvement but paid "tribute" to Ayatollah Khomeini's "order" to carry out the purge.
Khomeini died in 1989.
In early May, more than 150 personalities, including Nobel Prize winners, former heads of state and former UN officials, called for an international investigation into the 1988 executions.
Hamid Noury is also charged with having participated in the execution of other prisoners during the same period on the basis of their ideology or belief, considered opponents of the "theocratic Iranian state", according to the prosecution.
The court will hear dozens of witnesses over three days of sittings, which begin at 9.15 (07.15GMT) on Tuesday, with a verdict expected in April 2022.