Police officials said the explosion on Friday morning took place in Tahrawa, a village inhabited by families from the Shabak ethnic group. The village is near the city of Mosul, 360 kilometers (225 miles) northwest of Baghdad. Police say about 37 people were wounded in the attack.
The Shabak have their own distinct language and belief system.
Hospital officials confirmed the toll from the attack. All officials spoke on condition of anonymity because they were not authorized to release details to journalists.
According to the United Nations, 8,868 people were killed in Iraq last year - the country's highest death toll since the peak of sectarian bloodletting in 2007.