Iraqi officials say at least 11 people were killed and several others wounded in violence Friday, as Shi'ite Muslims and Christians observed religious holidays.
In the eastern Baghdad district of Sadr City, Iraqi officials say a roadside bomb blast killed six Shi'ite Muslim worshipers as they observed the solemn Ashura holiday.
Police have stepped up security in Iraq to prevent attacks against Shi'ites during Ashura, and minority Christians celebrating Christmas.
At least four people were wounded during clashes between Christians and ethnic Shabak men in the northern town of Bartala. Security officials say the fighting erupted when young men threw stones at a church.
Elsewhere in northern Iraq, police say at least four people were killed in separate acts of violence in Mosul, including three census workers shot and killed by unidentified gunmen.
Also, officials say a car bombing killed at least one Kurdish soldier in the town of Rabiyaa near the border with Syria.
Iraqi authorities had increased security in areas with significant Christian populations after receiving reports of possible attacks against the minority group during the Christmas holiday.
More than 25,000 Iraq police and soldiers have also been deployed to protect Shi'ite pilgrims who are observing Ashura.