A roadside bomb explosion killed a Shiite pilgrim and wounded five others in southern Baghdad on Wednesday, an Interior Ministry source said.

"An explosive charge went off near a group of Shiite pilgrims who were traveling on foot in Baghdad southern district of Zaafaraniyah on their way to the holy city of Karbala, some 110 km southwest of Baghdad," the source told Xinhua on condition of anonymity.

On Sunday, two Shiite pilgrims were killed and 11 others injured when two bomb explosions hit a group of them during their days-long march to Karbala shrine for a major religious gathering.

Hundreds of Shiite pilgrims are marching from different Iraqi provinces to the holy city of Karbala to commemorate Arbaeen ritual which is the end of 40 days of mourning for Imam Hussein, grandson of Prophet Muhammad.

Major Shiite commemorations have frequently been targeted in the past by suspected Sunni insurgents led by al-Qaida in Iraq in their drive to incite sectarian violence in the war-torn country.