The death toll in a new spate of bombings on Shiite pilgrims in Iraq has risen to 56, officials confirmed.
Authorities in the holy city of Karbala, 55 miles south of the capital Baghdad, said the attacks also injured an estimated 180 people, 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 into Karbala. Most of the victims were Shiite pilgrims travelling to observe annual religious rituals.
It was the latest in a wave of attacks in recent days as insurgents test Iraqi security forces ahead of the planned US withdrawal at the end of the year. There was no immediate claim of responsibility but the methods and targets were typical of al Qaida and other Sunni-dominated extremist groups.
Police and soldiers lined main Baghdad roads on Friday morning as thousands of pilgrims headed to attend annual religious rituals
The Karbala bombings were the latest in a barrage of attacks across the country that have killed more than 120 people since Tuesday.
On Thursday, a suicide bomber rammed his explosives-packed car into the front gate of a police headquarters in the eastern city of Baqouba, killing three. An earlier strike on Shiite pilgrims walking to Karbala from Baghdad killed one and wounded 10.
The series of attacks shattered a relative calm since the formation last month of a new government under prime minister Nouri al-Maliki, a Shiite whose family comes from the Karbala area.