Adel Abdel Mahdi joined Muhandis associate Hadi al-Ameri, Shiite cleric Ammar al-Hakim, former premier Nuri al-Maliki and other pro-Iran figures in a large crowd.

The coffins were first brought to a revered Shiite shrine in Baghdad's Kadhimiya district, where thousands of mourners chanted "Death to America."

The crowds then accompanied them south to a point near the Green Zone, home to government offices and foreign embassies, including America's.

The dignitaries then accompanied the coffins into the Green Zone for an official ceremony.

Soleimani and Mohandis were killed along with eight others in a precision drone strike early Friday as they drove away from Baghdad international airport in two vehicles.

Soleimani was the head of the Iranian Revolutionary Guards' foreign operations arm while Muhandis was the deputy head of Iraq's Hashed al-Shaabi paramilitary network.

Their deaths sparked fears of a looming proxy war between Iran and the United States on Iraqi soil, further fanned by a new strike on pro-Iran factions on Saturday.

The Hashed, many of whose factions have close ties to Iran, said a strike had targeted one of their convoys.

State television said the attack was American. But the US-led coalition in Iraq said it was not involved.