Mourners hold posters of late Iranian President Ebrahim Raisi during a funeral ceremony for him and his companions who were killed in a helicopter crash at Mosalia mosque in Tehran.AFP
In the city centre, mourners clutching portraits of Raisi gathered in and around the University of Tehran, where Iran's supreme leader, Ayatollah Ali Khamenei, led the prayers.
Flanked by top officials, Khamenei said prayers over the coffins of the dead, who also included Foreign Minister Hossein Amir-Abdollahian.
The leader of the Palestinian group Hamas, Ismail Haniyeh, joined the procession, as did the deputy leader of the Lebanese group Hezbollah, Naim Qassem.
"I say once again... we are sure that the Islamic Republic of Iran will continue its support for the Palestinian people," Haniyeh told the crowd.
Raisi's helicopter crashed into a fog-shrouded mountainside in northwestern Iran on Sunday as he headed back to the city of Tabriz after attending a ceremony on the border with Azerbaijan.
A huge search and rescue operation was launched, involving help from Turkey, Russia and the European Union. State television announced Raisi's death early on Monday.
Raisi, who was widely expected to succeed Khamenei as supreme leader, was 63.
In the capital, huge banners have gone up hailing the late president as "the martyr of service", while others bade "farewell to the servant of the disadvantaged".
Tehran residents received phone messages urging them to "attend the funeral of the martyr of service".
From the university, the coffins will be driven to the huge Enghelab Square in the city centre and on to Azadi Square, state media said.
Burial in Mashhad
Funeral rites for Raisi and his entourage began on Tuesday with processions through Tabriz and the Shiite clerical centre of Qom drawing tens of thousands of black-clad mourners.
From Tehran, the bodies will be taken to Iran's second city of Mashhad, Raisi's hometown in the northeast, where he will be buried on Thursday evening after funeral rites at the Imam Reza shrine.
Khamenei, who wields ultimate authority in Iran, has declared five days of national mourning and assigned vice president Mohammad Mokhber, 68, as caretaker president until a June 28 election for Raisi's successor.
Iran's top nuclear negotiator Ali Bagheri, who was Amir-Abdollahian's deputy, has been named acting foreign minister.
The country's armed forces chief of staff Mohammad Bagheri has ordered an investigation into the cause of the helicopter crash.
Raisi was elected president in 2021, succeeding the moderate Hassan Rouhani at a time when the economy was battered by US sanctions.
After his death, global allies Russia and China sent their condolences, as did NATO, while the UN Security Council observed a minute's silence.
Messages of condolence also flooded in from around the world, including Saudi Arabia, and Egypt.
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