At least 40 people were killed today when a suicide bomber detonated an explosive vest amid a crowd of Shiite pilgrims during a trek south of Baghdad. A tent where the marchers stopped for food exploded in Iskandariyah in the second attack on Arbaeen, a day when millions descend on Karbala to honor the grandson of the prophet Muhammad, who is buried there.
Earlier, three pilgrims were killed in a sniper-and-bomb attack in Baghdad. Some 40,000 police officers and military troops were deployed to protect the pilgrims from expected attacks by Sunni insurgents. The violence occurred as Iraqi Prime Minister Nouri al-Maliki traveled to London for a second round of medical tests following an illness two months ago. A spokesmen described it as a routine examination that confirmed he was in good health. (Read more Iraq stories.)