Iraq's joint operations command said another 19 people were also wounded, calling it a "preliminary toll."

Medical sources told AFP they feared the death toll could be twice as high as officially announced. The health ministry said it had mobilised medics across the capital to respond to the deadly attack.

Military spokesman Yahya Rasool said two suicide bombers detonated their explosives as they were being pursued by security forces.

An AFP reporter at the scene said the bombers had struck a huge open-air market for second-hand clothes in Tayaran Square.

It had been teeming with people following nearly a year of restrictions imposed in a bid to halt the spread of Covid-19.

Security forces cordoned off the area and paramedics were working to help the casualties.

After years of deadly sectarian violence, suicide bombings have become relatively rare in the capital. The last such attack took place in June 2019 and left several people dead.

In January 2018, a suicide bombing in Tayaran Square killed more than 30 people, just a few months before the last parliamentary election.

Elections in Iraq are typically preceded by escalating violence, including bombings and assassinations.

Iraq is gearing up for a new general election this year, which Prime Minister Mustafa al-Kadhemi originally set for June -- nearly a year ahead of schedule -- in response to widespread protests in 2019.

But authorities are in talks to reschedule them for October in order to give electoral authorities more time to register voters and new parties.

Thursday's twin attack was not immediately claimed but suicide bombings have been used by ultra-conservative Islamist groups, most recently the Islamic State organisation.

Iraq declared IS defeated at the end of 2017 after a fierce three-year campaign to retake the one-third of the country that had been seized by the jihadists.

But the group's sleeper cells have continued to operate in desert and mountain areas, typically targeting security forces or state infrastructure with low casualty attacks.

Still, the US-led coalition that had been supporting Iraq's campaign against IS has significantly drawn down its troop levels over the past year, citing the increased capabilities of Iraqi troops.

The United States, which provides the bulk of the force, has 2,500 troops left in Iraq -- down from 5,200 a year ago.

They are mainly in charge of training, providing drone surveillance and carrying out air strikes while Iraqi security forces handle security in urban areas.