Iraq hanged 21 convicted terrorists and murderers as air raids on ISIS strongholds in Diyala province intensified on Tuesday.
Since 2018, Iraq has put hundreds of suspected terrorists on trial and conducted mass executions after victory was claimed over the extremists.
The hangings, carried out on Monday, took place at Nasiriyah prison in the south of Iraq, according to the interior ministry.
Nasiriyah is known for holding former officials of Saddam Hussein's regime, which was toppled by the 2003 US-led invasion.
Saddam was hanged in December 2006 for crimes against humanity.
The men hanged on Monday were convicted under a 2005 counter-terrorism law.
Authorities did not give details about the specific crimes, but the interior ministry said some of those executed were involved in two attacks that killed dozens of people in the northern town of Tal Afar.
The statement gave no detail about the identity of those executed.
Human rights groups accuse Iraq of inconsistencies in the judicial process and flawed trials leading to unfair convictions.
Amnesty International and other rights groups said Iraq's justice system is marred by corruption, with judges carrying out rushed trials involving circumstantial evidence.
They said the accused did not have a proper defence or access to lawyers.
Iraq said its trials are fair.
Dozens of foreign citizens suspected of belonging to ISIS have been tried by Iraqi courts. Of those, 11 French citizens and one Belgian were sentenced to death.
They are awaiting execution.
According to Amnesty, Iraq ranks fifth among countries that carry out death sentences.
In 2014, ISIS captured a third of Iraq, but a US-backed military campaign largely defeated the group in Iraq and neighbouring Syria after a three-year battle.
The development came as Iraqi air forces attacked an ISIS headquarters in the Al Zour region on the northern Diyala River in Khanaqin.
Security forces in the province have retreated significantly over the past few weeks, amid calls for a major military campaign to disarm militias and combat ISIS sleeper cells.