msnbc.com news services report:
Majid Hussein, a government employee, was one of the pilgrims heading to the shrine. He said people began running away in panic when they heard a loud explosion.
"I saw several dead bodies and wounded people, including children on the ground asking for help. There were also some baby strollers left at the blast site," he said.
"A terrorist wearing a police uniform and carrying fake police I.D. managed to reach a police checkpoint and blew himself up among police and pilgrims," a police official at the scene of the bombing said.
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