Car bombs and a suicide attack in two Iraqi towns north of Baghdad have left at least 21 people dead.

No group claimed responsibility for the attacks.

However, Iraqi officials blame most of the sectarian violence that has killed nearly 2,000 people since April on Sunni Islamist insurgents linked to al-Qaeda.

Officials said two car bombs exploded and a suicide bomber in another vehicle detonated his explosives in a food market in the mostly Shia Muslim town of Jadidat al-Shatt in Diyala province, which is 40km north of Baghdad.

The triple blasts left 13 dead and more than 50 wounded among the wreckage of fruit and vegetable stalls, local officials and police said.

Another car bomb hit a market in the religiously-mixed town of Taji, 20km north of Baghdad, killing at least eight more people.

Iraqi police also defused bombs planted at two oil wells near the northern city of Kirkuk.