KARBALA (AFP) – A suicide attacker driving a minibus on Wednesday ploughed into a crowd of Shiite pilgrims in central Iraq, killing 20, in the second deadly assault on devotees this week.

The bomber struck pilgrims walking on foot on the outskirts of the shrine city of Karbala, 110 kilometers (68 miles) south of Baghdad, where Shiites are massing to observe Arbaeen rituals. The attack also left 117 people wounded.
Arbaeen marks 40 days after the Ashura anniversary commemorating the martyrdom of one of Shiite Islam's most revered figures, Imam Hussein, by the armies of Yazid in 680 AD.
A senior health official in Karbala who gave the toll said at least one woman and three children were among the dead. The wounded are being treated at two hospitals in the city.
An interior ministry official, who confirmed the casualty toll, said the bomber detonated an explosives-laden bus.
The victims had been traveling from Hilla in Babil province and were among tens of thousands of Shiites, including many from neighboring Iran, heading to pay homage at Imam Hussein's shrine in Karbala, one of the holiest places in Shiite Islam.
Worshippers continued to flock into the city on Wednesday despite the attack, said an AFP correspondent in the city, where tens of thousands of police and soldiers have been deployed to safeguard the ceremonies.
Television pictures showed crowds on roads stretching into the far distance, walking as a sign of piety, and carrying flags adorned with Imam Hussein's image.
Wednesday's attack followed that of a female suicide bomber on Monday who blew herself up among a crowd of pilgrims who were making their way to Karbala for the rituals, killing at least 41 people and leaving more than 100 wounded.
Around 30,000 members of the Iraqi security forces are on duty in the holy city for the festival which culminates on Friday.
Prime Minister Nuri al-Maliki's office blamed Monday's suicide bombing on the Baath party of executed dictator Saddam Hussein.
""We hold Baathists and their Takfiri allies responsible for this massacre,"" Maliki said.
Takfiri is a term used by the Iraqi government to refer to Al-Qaeda members.
Defense ministry spokesman General Mohammed al-Askari said the woman bomber came from Diyala province, northeast of Baghdad, that has in the past been a stronghold of Al-Qaeda which still has a local presence.
Iraqi politicians and U.S. forces have warned of rising violence ahead of a general election on March 7, the second parliamentary ballot since the U.S.-led invasion of 2003 which toppled Saddam before ushering in a deadly insurgency.
In recent months, insurgents had appeared to direct their attacks away from religious targets to government buildings in Baghdad.
The apparent switch had prompted the army to urge government officials to change their travel itineraries and avoid high-risk areas in the capital, the Baghdad military command said on Monday.
Photo: Shiite pilgrims walk towards the city of Karbala to attend the Al-Arbain Shiite ritual in Baghdad February 2, 2010. (Reuters photo)-