Twenty-one people convicted of terrorism, including three women, were executed Tuesday in the latest of a string of executions by Iraqi officials, CNN reported.
The United Nations said Iraq has executed 90 people since November, most of them in the first 40 days of the year.
Human rights groups said they were concerned about the large number.
Joe Stork, deputy Middle East director at Human Rights Watch, said the charge of terrorism was too broad to define of what the people were really convicted. He added that trials in Iraqi courts were "very problematic."
U.N. High Commissioner for Human Rights Navi Pillay earlier this year expressed concern about the "terrifying number" of mass executions.
"Most disturbingly, we do not have a single report of anyone on death row being pardoned, despite the fact there are well documented cases of confessions being extracted under duress," Pillay said.
Iraq announced Monday the release of 625 inmates who had completed their sentences.