21 Shia pilgrims killed by bombs
Twenty-one people have died and nearly 100 others were injured when five bombs struck Shia pilgrims during an important religious ritual.
The attacks revealed the enormous security challenges that still beset Iraq as the US military leaves the country.
Shia religious holidays such as the mourning period known as Ashoura are targeted every year by Sunni extremists and have become especially difficult tests for the US-trained Iraqi security forces, still struggling to protect their citizens.
The US military is rapidly shipping troops and equipment out of the country before a December 31 deadline to have all its forces out - then the entire responsibility for the nation's security will rest with Iraq's leaders.
On Ashoura, the hundreds of thousands of pilgrims who walk to the southern holy city of Karbala from around the country in a show of religious Shia fervour present a particularly easy target for Sunni militants who do not consider Shias to be true Muslims.
After the fall of Saddam Hussein's Sunni-dominated regime in 2003, Shias regained the right to express their beliefs freely, and since then the annual commemorations have drawn huge crowds despite the threat.
In the first attack, a bomb exploded among Shia pilgrims in Latifiyah, about 20 miles south of the capital, killing two of them and wounding three others, police said. A medical official confirmed the casualty toll.
Hours later, a car bomb exploded near a group of pilgrims in the town of Mahaweel as they were heading to Karbala, killing eight people and wounding about 56 other pilgrims, said police officials in Babil province. Mahaweel is about 35 miles south of Baghdad.
Three more attacks against Shia pilgrims in the capital killed 11 people and wounded 41 others, police said.
Ashoura marks the anniversary of the seventh-century death of Imam Hussein, a grandson of the Prophet Muhammad. His death in a battle outside of Karbala sealed Islam's historical Sunni-Shia split, which still bedevils the Middle East and Iraq in particular. To commemorate his death, Shias walk from around the country to Karbala.