Those attacks included a coordinated assault on a private Shiite college in Baghdad in which a suicide bomber with an explosives belt attacked the main gate while three militants attacked the back gate of the college. Four policemen and one teacher were killed and 18 other people were wounded.
Hours after the attack, an al-Qaida spin-off group known as the Islamic State of Iraq and the Levant claimed responsibility for the attack, accusing the college's professors of teaching students to "curse" the Prophet Muhammad and training them to "fight" the Sunnis in Iraq and Syria.
The authenticity of the statement could not be independently verified, but its style was consistent with previous statements.
The U.N. Special Representative in Iraq, Nickolay Mladenov, described the college assault as a "vicious and cowardly attack on innocent civilians."
"This is yet another example of sectarian-based violence that the people of this country need to fight in order to bring this country to tranquility," Mladenov said in a statement. "The target has been selected to incite sectarian hatred, with utter disregard for human life and religious values," he added.
According to the United Nations, 8,868 people were killed in Iraq last year — the country's highest death toll since a peak of sectarian bloodletting in 2007.
Associated Press writer Murtada Faraj contributed to this report.
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