A car bomb in a restive town north of Baghdad on Friday killed 17 Iranian pilgrims, the latest in a spike in violence that has sparked fears of all-out sectarian war. A further 45 worshippers were wounded in the attack, which struck their bus as it was passing through the town of Muqdadiyah en route from the Iranian border to the holy Shiite city of Najaf. Investigation for the cause of the attack is underway. Iranian pilgrims coming to Iraq to visit holy shrines and religious sites of Shi’ite often become the attack target of Sunni Muslim gunmen.