Police sources said that the suicide bombers were riding motorcycles and blew themselves up in a crowded mobile phone market in Sadr City, wounding more than 100 people in addition to the dead.
A witness saw pools of blood on the ground with slippers, shoes, and mobile phones at the site of the blasts, which was sealed off to prevent further attacks.
In a statement circulated online, IS said that it was responsible for the blasts.
“Our swords will not cease to cut off the heads of the rejectionist polytheists, wherever they are,” it said, using derogatory terms for Shia Muslims.
Iraqi forces backed by airstrikes from a US-led coalition have driven IS back in the western Anbar province recently and are preparing for an offensive to retake the northern city of Mosul.
However, the militants are still able to strike outside territory they control, often targeting members of Iraq’s Shia majority, most recently on Thursday, when two IS suicide bombers killed 15 people at a mosque in the capital.
At dawn yesterday, suicide bombers and gunmen attacked Iraqi security forces in Abu Ghraib, seizing positions in a grain silo and a cemetery, and killing at least 17 members of the security forces, officials said.
Security officials blamed IS, and a news agency that supports the group said that it had launched a “wide attack” in Abu Ghraib — some 25km from the centre of Baghdad and next to the international airport.
Death toll in Baghdad twin suicide bombing rises to 70: sources https://t.co/6K43kRqc6t— Reuters (@Reuters) February 28, 2016