A legal complaint called Monday for Swiss authorities to arrest Iran's president during an expected visit and charge him with crimes against humanity connected to a 1988 purge of dissidents.
The complaint asks Swiss federal public prosecutor Andreas Muller to ensure the arrest and prosecution of Iranian President Ebrahim Raisi "over his participation in acts of genocide, torture, extrajudicial executions and other crimes against humanity".
Raisi was expected to participate in the United Nations Global Refugee Forum, which begins in Geneva on Wednesday, but the UN said Monday evening that Foreign Minister Hossein Amir-Abdollahian would lead the Iranian delegation, an indication that Raisi might not show.
The legal complaint against him, seen by AFP, was dated Monday. The prosecutor's office did not immediately confirm that it had been received.
It was filed by three alleged victims from Iran's crackdown on dissidents in the 1980s.
Rights groups have long campaigned for justice over alleged extrajudicial executions of thousands of mainly young people across Iranian prisons within a few months in the summer of 1988, just as the war with Iraq was ending.
Those killed were mainly supporters of the People's Mujahedin Organization of Iran, known by the abbreviations MEK or PMOI, a group considered a terrorist organisation by Iran that backed Baghdad during the conflict.
The petitioners behind Monday's complaint said they could personally identify Raisi as figuring on a commission that sent thousands of jailed opponents to their deaths during the crackdown.
He was serving as deputy prosecutor general of Tehran at the time, and was among the most eager on his commission to sentence prisoners to death, the complaint said.
The main petitioner, Reza Shemiriani, was arrested in 1981 and was one of fewer than 150 of the 5,000 prisoners detained in his cell bloc who survived the 1988 purge, according to the complaint.
Raisi had asked him what group he belonged to, and when he said MEK, "his death sentence was assured", the complaint said, adding that Shemiriani still did not know why his life was spared.
Instead he remained in prison until 1991, facing daily torture, the complaint said.
The two other petitioners had also been in Iranian prisons in 1988, and said they recognised Raisi "as a member of the death commission", according to the complaint.
- International campaign -
In parallel to the legal complaint, an international campaign is also underway expressing outrage at Raisi's participation in the UN refugee forum, and urging his prosecution for "involvement in past and ongoing crimes under international law".
"Raisi was a key perpetrator of the 1988 massacre of thousands of political prisoners. His presence at the UN forum contradicts the fundamental values the UN stands for," said the petition.
So far it has gathered more than 200 signatures from dignitaries including Nobel laureates, judges, former ministers, parliamentarians, academics and UN rights experts.
"We firmly believe that the United Nations, as a bastion of human rights and justice, should not compromise its reputation by extending an invitation to an individual accused of grave human rights violations," it said, urging the UN to "promptly rescind its invitation to Raisi".
When asked about the petition, forum host UNHCR, the UN refugee agency, told AFP that "Iran is a member state of the United Nations and therefore invited to the Global Refugee Forum".
"Iran has also been one of the largest refugee hosting countries for over 40 years," a spokesman said in an email, adding that "the Iranian delegation will be led by the foreign minister".