Thousands of Iranians attended a funeral procession for top military general Qasem Soleimani and Iraqi militia leader Abu-Mahdi al-Muhandis in the capital Tehran on Monday.

Soleimani, the head of Iran's Revolutionary Guards' elite Quds force, and al-Muhandis, the deputy leader of the Iraqi Hashd al-Shaabi force, were killed in a U.S. drone airstrike outside Baghdad airport on Friday.

Iran's Supreme Leader Ali Khamenei led the prayer for the two men at the University of Tehran, according to the official IRNA news agency.

Thousands of mourners chanted "Death to America" and "Death to Israel" as they carried banners demanding revenge for Soleimani.

The corpses of Soleimani and al-Muhandis arrived in Tehran Monday dawn along with the bodies of four other people killed in the U.S. airstrike.

On Saturday, thousands of mourners gathered in several Iraqi cities for a funeral procession for the two men.

Soleimani's killing marked a dramatic escalation in tensions between the U.S. and Iran, which have often been at a fever pitch since President Donald Trump chose in 2018 to unilaterally withdraw Washington from a nuclear pact world powers struck with Tehran.

Iran's top security body has vowed "harsh retaliation" at the "right time and right place" to the general's killing.

The Pentagon accused Soleimani of plotting an attack on the U.S. Embassy compound in Baghdad, and planning to carry out additional attacks on U.S. diplomats and service members in Iraq and the region.