Huge crowds have packed the streets of the Iranian capital Tehran for the funeral of military commander Qasem Soleimani.
Soleimani was assassinated in a US drone strike in Iraq on Friday on the orders of President Donald Trump.
Iran's Supreme Leader Ayatollah Khamenei led prayers and at one point was seen weeping.
Iran has vowed "severe revenge" for the death of Soleimani and on Sunday pulled back from the 2015 nuclear accord.
Soleimani, 62, headed Iran's elite Quds Force, and was tasked with protecting and boosting Iran's influence in the Middle East.
He supported Syria's President Bashar al-Assad in the country's civil conflict, aided the Shia militant group Hezbollah in Lebanon, and guided Iraqi militia groups against the Islamic State group.
The US saw him as a terrorist, and President Trump said Soleimani was plotting "imminent" attacks on US diplomats and military personnel.
In Iran, Soleimani was hailed as a national hero and widely considered the second most powerful man in the country behind Supreme Leader Khamenei.
But not all Iranians are as distressed about the general's death as the mourners who lined Tehran's streets, says BBC Middle East Editor Jeremy Bowen.
Soleimani was a hardliner and a dominant force in a regime that shot dead scores of protesters at the end of 2019. He also spent vast sums building up alliances and militias in Lebanon, Yemen, Iraq and Syria at a time when US sanctions are impoverishing many Iranians, our correspondent says.