The blast at a Sunni mosque in the northern city of Kirkuk also wounded 19 people, the sources said.
Eid al-Adha, which commemorates the willingness of Abraham (Ibrahim in Arabic) to sacrifice his son at God's command, is the biggest Muslim holiday of the year.
Militants in Iraq have carried out numerous attacks on both Sunni and Shiite mosques this year, raising fears of a return to the all-out sectarian conflict that peaked in 2006-2007 and killed tens of thousands of people.
