Iraqi police and hospital officials say the death toll in a spate of bombings on Shiite pilgrims has risen to 56.
Iraqi police and soldiers lined main Baghdad roads on Friday morning as thousands of pilgrims headed to attend annual religious rituals in the holy Shiite city of Karbala, 55 miles (80 kilometers) south of the capital.
Authorities in Karbala said the attacks also wounded an estimated 180 - including about 25 members of the security forces.
The attacks were launched by three suicide bombers who blew up their cars near security checkpoints on at least two roads to Karbala.
There was no immediate claim of responsibility, but the methods and the targets were typical of al-Qaida and other Sunni-dominated extremist groups.