Islamic State militants have claimed responsibility for several suicide bombings that have killed at least 21 people and wounded dozens in two cities in northern Iraq.
The deadly attacks came as Iraqi government forces battled Islamic State (IS) militants to retake the northern city of Mosul, Iraq's second largest city.
The attacks in the cities of Tikrit and Samarra on November 6 appeared to be part of a series of diversionary attacks by the extremist group.
IS issued a statement claiming the attacks, but said there were three suicide bombers: two who struck Samarra and the third who attacked Tikrit.
Iraqi officials spoke of only two bombers.
In Tikrit, officials said a bomber detonated his explosives-laden ambulance at the southern entrance to the city during the morning rush hour, killing 13 people.
Officials also said another attacker detonated a vehicle in a car park for pilgrims visiting a Shi’ite shrine in Samarra, killing at least eight people, including several Iranian pilgrims.
Authorities in both cities declared curfews, fearing possible further attacks.
