Tens of thousands of supporters of Iranian-backed Iraqi paramilitary groups chanted anti-American slogans in central Baghdad on Sunday to mark the anniversary of the U.S. killing of Iranian General Qassem Soleimani and an Iraqi militia commander.

The gathering coincided with increasing tensions between Iran and the United States in the last days of President Donald Trump's administration, and many in the crowd demanded revenge.

Soleimani, head of an elite overseas unit of Iran's Revolutionary Guards, was killed along with Iraqi militia leader Abu Mahdi al-Muhandis on Jan. 3, 2020, in a U.S. drone strike on his convoy at Baghdad airport.