Gunmen have detonated suicide vests inside a shopping complex in Baghdad, and a car bomb has exploded nearby, killing at least 18 people in attacks claimed by Islamic State.

Two bombs later went off in the eastern town of Muqdadiya, killing at least 20 people and wounding another 50, security and medical sources said. Another blast in a southeastern Baghdad suburb killed seven more.

Islamic State claimed responsibility for the mall attacks, which it said had targeted a gathering of “rejectionist heathens”, its derogatory term for Shi’ite Muslims.

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The Iraqi government last month claimed victory against the hardline Sunni militants in the western city of Ramadi and have slowly pushed them back in other areas.

Monday’s attacks left the biggest death toll in three months.

Seven people, including two policemen, were killed in the car bomb blast near the Jawaher mall in the predominantly Shi’ite district of Baghdad Jadida, police and medical sources said.

Five more people were shot dead by the gunmen storming the mall, and six others were killed when those same assailants detonated their explosive vests.

Police regained control of the mall, and a senior security official told state television there were no hostages, rejecting reports that there had been people held.

As well as the violence meted out by Islamic State, Iraq is also gripped by a sectarian conflict mostly between Shi’ites and Sunnis that has been exacerbated by the rise of the militant group.

At least seven people were killed when a suicide bomber driving a car attacked a commercial street in Baghdad.

Earlier in the day, three people were killed and eight others wounded when a car bomb claimed by Islamic State went off near a restaurant in Baquba, while two bombs exploded in an area frequented by Shi’ite militia fighters in the town of Muqdadiya, killing 20.