Clashes in Iraqi capital of Baghdad have left at least 11 people dead and several other wounded as tensions are raising in the country due to renewed militants activities.

Two car bombs exploded near police checkpoints at the entrance to the district of Hussainiya in the north of the city, killing one policeman and seven civilians.

A third bomb near a restaurant frequented by police killed three civilians in the southern district of Doura, medics and police said. At least 33 people were wounded in the three attacks.

No group immediately claimed responsibility for the blasts.

Iraq has become increasingly volatile after militants carried out several attacks in different parts of the country that broke out initially in April, in the northern town of Hawijah.

Iraqi officials have repeatedly said that insurgent groups, such as al-Qaida in Iraq and supporters of former Iraqi dictator Saddam Hussein's regime, have infiltrated the demonstrations.

April was the deadliest month for Iraq in nearly five years, with more than 700 people killed in violent attacks across the country.