BAGHDAD (AP) -- A car bomb explosion tore through a crowd of Shiite pilgrims returning home Thursday from a religious commemoration, killing at least 20 and reinforcing fears of renewed sectarian violence, according to Iraqi officials.
The blast erupted late in the afternoon in the town of Musayyib, about 60 kilometers (40 miles) south of the Iraqi capital. It targeted worshippers returning from the Shiite holy city of Karbala following the climax of the religious commemoration known as Arbaeen.
Children were among the 20 people confirmed killed, according to a police official. He said at least 50 people were wounded.
The bomb went off in the middle of a gathering of pilgrims changing buses coming from Karbala on their way to other destinations in the country, according to police.
"The explosion shook the whole block and smashed the windows of my house," said teacher Ibrahim Mohammed, who lives nearby. "I ran to the scene of the explosion only to find charred bodies and burning cars. There were women screaming and searching for their missing children."
A hospital official confirmed the casualty toll. The officials spoke on condition of anonymity because they were not authorized to release the information to reporters.
Thursday marked the height of Arbaeen, when hundreds of thousands of Shiite pilgrims converged on Karbala to mark the passing of 40 days after the anniversary of the seventh century martyrdom of the revered Shiite saint Imam Hussein, the grandson of the Prophet Muhammad.
Shiite pilgrims are one of the favorite targets for Sunni insurgents during Shiite religious events.
Iraqi authorities typically tighten security in Karbala and along routes used by pilgrims, but security forces acknowledge they are unable to prevent all attacks.
As in previous years, the pilgrims practiced the ritual of self-flagellation on the streets, hoisted Shiite religious flags on trees and lamp posts and served food from tents pitched on street corners.
Zaid Mohammed, a 21-year old student, said he walked to Karbala from a nearby city to show his deep respect for Imam Hussein.
"All the people came here to show their gratitude and appreciation for the sacrifices made by Imam Hussein while fighting injustice," he said. "We have decided to confront all the security risks that we might face on our way to Karbala."
State television earlier Thursday aired video of Prime Minister Nouri al-Maliki walking among the pilgrims.
Thursday's attack came after Iraqi authorities ordered the release of 11 women facing criminal charges and pledged to transfer other women prisoners to jails in their home provinces
The move appeared aimed at addressing a main demand during a wave of protests by the country's Sunni minority against the Baghdad government.
The demonstrations erupted following the arrest of bodyguards assigned to Finance Minister Rafia al-Issawi, one of the central government's most senior Sunni officials. The protests tap into deeper Sunni feelings of perceived discrimination and unfair application of laws against their sect by Shiite Prime Minister Nouri al-Maliki's government.
Vice President Tariq al-Hashemi, another high-ranking Sunni official, is living in exile in Turkey after he was handed multiple death sentences in absentia for allegedly running death squads, a charge he dismisses as politically motivated.
Justice Ministry spokesman Haider al-Saadi said the families of the imprisoned women can secure their release by paying bail. He added that 13 Sunni women convicted on criminal charges will be transferred from a Baghdad jail to prisons in their home provinces of Anbar, Salahuddin and Ninevah to serve out their sentences.
The detention of female prisoners has been a focus of the demonstrations, but it was not clear whether the decision to release some of them will satisfy the protesters.
Associated Press writer Adam Schreck contributed.
Copyright 2013 The Associated Press.