A blast killed five pilgrims and wounded 15 in northeastern Iraq during a Shi'ite religious observance, Iraqi authorities said Sunday morning.
A police official said that the bomb exploded in Tuz Khormato, north of Baghdad, as pilgrims were gathering to mark the last day of Ashoura. A medical official confirmed the casualties.
The attack came at the climax of a 10-day mourning period for Shi'ites marking the 7th Century death of the Prophet Muhammad's grandson, Imam Hussein.
Pilgrims have come under repeated attack by insurgents seeking to re-ignite sectarian violence that brought the country to the brink of civil war two years ago.
Both officials spoke on condition of anonymity as they were not authorized to release information.