A triple car bombing in a Kurdish-controlled Iraqi town has killed an estimated 28 people, many of whom were peshmerga veterans re-enlisting to fight against Islamic State militants.

The attack took place early on Sunday morning at a government compound in Qara Qubah, near Baqubah city, with civilians and soldiers among the dead. Another 90 people were injured.

"There are still victims trapped in the debris," one official warned.

The attack on peshmerga fighters came shortly after it emerged British Army trainers were deployed to Irbil in order to help Kurdish forces use heavy machine guns against IS.

It also came as the police chief of Anbar province, Gen Ahmed al Dulaimi, died as he travelled in a convoy.

Iraq's interior ministry described him as a "hero who set a good example for self-sacrifice".

Islamic State fighters have seemingly claimed responsibility for the attacks on Twitter, adding that three of the bombers were non-Iraqis who had been sent from Germany, Saudi Arabia and Turkey.

Pro-government security forces recaptured parts of Anbar from the al Qaeda breakaway group on Saturday, after months of battling with IS fighters.

"The general was out on patrol in the military parameter of al Bu Risha, checking on the sectors where the confrontations with Islamic State insurgents are taking place," one official told Reuters. "His convoy was targeted by two improvised explosive devices."

It remains unclear if other members of his convoy were killed in the bombing.

The explosions followed a bloody day of violence in Baghdad on Saturday, with more than 45 people losing their lives in a series of bombings that rocked Iraq's capital city.

Three bombs were detonated in busy shopping areas.

The first killed eight people outside an ice cream shop. Just metres down the road in the neighbourhood of Shaoula, another car blast killed 18 people.

And in countryside north of the city, a bomber wearing a suicide vest left 11 others fatally wounded.