Bomb attacks claimed by the Islamic State jihadist group killed at least 14 people and wounded 55 others Thursday in the Iraqi capital, security and medical officials said.

One of the two attacks struck close to the entrance of a marketplace near Tayran Square. Most of the victims were civilians but at least one policeman was among the dead.

The other hit the central Wathba Square, outside government officers where retired people were queueing to collect their pensions.

Police said the bombings took place less than 25 minutes apart.

IS, which overran swathes of Iraq in June 2014, claimed the bombings in an online statement.

The jihadist group said the attacks were carried out by two suicide bombers, whom it did not identify.

Both Tayran and Wathba squares are in mixed Sunni-Shiite neighbourhoods, and the motive for the bombings was not clear.

IS frequently targets Iraq's majority Shiites, whom it considers heretics, fuelling sectarian tensions in the country, and often strikes areas such as markets and cafes where crowds gather.

The last major bombing in Baghdad was more than a month ago.

On August 15, a car bomb in a Shiite-majority area of north Baghdad where people gather to buy and sell vehicles killed 11 people and wounded at least 68.

That blast hit Sadr City, the same district where a massive truck bomb ripped through a wholesale vegetable market just two days before, killing at least 54 people.

Iraqi forces backed by a US-led coalition and Iran have regained significant ground from IS north of Baghdad, but much of the country's west remains outside government control.

Even before the IS offensive, bombings targeting civilians were a major threat, killing hundreds each month. The frequency of blasts in Baghdad has declined since last year's jihadist advance.