Fourteen people, including six Shi'ite worshippers, have been killed in a spate of attacks across Iraq on Friday, despite increased security for Christmas and Shi'ite rituals for Ashura.
Three teachers in northern Iraq are among the dead. Dozens of others have been wounded.
Iraqi authorities had stepped up security in the run-up to Christmas and Ashura, deploying more security forces in cities with significant Christian populations.
About 46,000 police and soldiers have also been deployed in the Shi'ite shrine cities of Najaf and Karbala.
Ashura is one of the most important dates in the Shia religious calendar.