BAGHDAD -- Attacks in the capital and the southern town of Hilla killed at least 26 in Iraq on Thursday and Friday, with religious-tinged violence ticking up as Christmas coincided this year with one of Shiite Islam's most important observances.

Ashura -- a 10-day commemoration of the death in the seventh century of the Prophet Muhammad's grandson, one of Shiite Islam's most revered figures -- culminates on Sunday. Hundreds of thousands of Shiite pilgrims stream into the Iraqi cities of Karbala and Najaf, providing a convenient target for sect-based violence.

Mourners at a funeral procession in Baghdad on Friday for a man killed in a car bomb attack.

Mourners at a funeral procession in Baghdad on Friday for a man killed in a car bomb attack.

Associated Press

Mourners at a funeral procession in Baghdad on Friday for a man killed in a car bomb attack.

Violence in the country is down markedly from its peak in 2006 and 2007. But high-profile bombings in Baghdad on three occasions since August have killed more than 100 people each, stoking security worries as U.S. forces prepare to draw down significantly next year.

Iraqis have been bracing for a rough late December, with Christmas and Ashura overlapping. Iraq's small Christian population has long been the target of religious violence.

Pope Benedict XVI mentioned the "tiny flock," at times "subject to violence and injustice," in his Christmas Day blessing on Friday, according to the Associated Press.

Christian officials in Iraq's southern city of Basra canceled celebrations. Throughout the country, churches observed low-key services amid worry over violence. On Thursday, Christians and Shiite Iraqis clashed north of Mosul, injuring five people.

Sunni and Shiite Muslims, meanwhile, have waged bloody battles against each other, though sectarian violence has fallen sharply over the past two years. Ashura commemorations in the past have been particularly bloody.

On Friday, Iraqi officials say, a roadside bomb killed six Shiite Muslim pilgrims in Sadr City in eastern Baghdad. The bombing detonated amid an Ashura procession and injured at least 17 others. A medic and a policeman confirmed the number of casualties to the AP.

Thursday's attacks also claimed an ally of Iraqi Prime Minister Nouri al-Maliki. Babil provincial council member Nama Jasim al-Bakri, a member of Mr. Maliki's State of Law political coalition, was killed during the turmoil that followed other violence.

A bomb left outside a shop at the bus station in the Bab al-Hussein district of Hilla, the capital of Babil province, exploded at around 1:20 p.m. on Thursday. Ashura pilgrims had gathered there to join buses to Karbala and Najaf.

After that bomb went off, the explosives directorate of the Babil police department dispatched officers to the bus station, according to the police official.

The officers became suspicious of a car parked near a group of taxis. As officers approached, the car exploded. At least 10 people were killed, including five police, and 110 were injured.

Mr. Bakri was killed as the car he was riding in approached a roadblock near the back of the bus station and near the police department.

He was shot after his car failed to stop at a checkpoint, causing a guard to mistake him for an attacker, police said, according to the AP.

Also Thursday, four people were killed and 13 injured in a bombing of Shiites in the eastern Baghdad area of Zafraniya.

A roadside bomb also killed five and injured 23 at a funeral procession, unrelated to the holiday, in Sadr City, the poor and densely populated area of Baghdad where Shiite cleric Moqtada Sadr has his base.