BAGHDAD — A suicide bomber attacked a bus carrying Shiite pilgrims home from Samarra on Saturday, killing at least 30 people in the latest of several recent assaults on pilgrims.
It was the second attack in three days against Shiite pilgrims near Samarra, whose gold-domed shrine was damaged in a 2006 bombing that led to waves of sectarian killings between Iraq’s Sunni and Shiite populations.
The bombing happened at one of about 40 checkpoints that line the road between Samarra and Baghdad, highlighting how easily attackers are able to exploit security flaws at the remote outposts. The checkpoints often cause traffic to back up, leaving vehicles open to attack.
According to security officials, the bus was stopped at a police checkpoint about 7 miles south of Samarra on Saturday afternoon when the bomber strode through the checkpoint and walked up to the vehicle’s open front door.
One report on Iraqi television said the attacker had been speaking with police officers seconds before he detonated his explosives vest.
There were no claims of responsibility, but security officials blamed al-Qaeda in Iraq, a Sunni group, and said the bombing highlighted flaws in Iraq’s intelligence gathering. The New York Times



