Baghdad - A suicide car bombing claimed by the Islamic State group ripped through a busy Baghdad shopping district on Sunday, killing at least 119 people in the deadliest attack this year in Iraq's capital.The blast hit the Karrada district early in the day as the area was packed with shoppers ahead of this week's holiday marking the end of the Muslim fasting month of Ramadan.It came a week after Iraqi security forces recaptured Fallujah from ISIS, leaving Mosul as the only Iraqi city under the jihadist group's control.The bombing also wounded more than 140 people, security officials said.Prime Minister Haider al-Abadi visited the site of the attack and vowed "punishment" for its perpetrators, his office said.The blast set buildings ablaze, and firemen were still working to extinguish them about 12 hours later.Men carried the bodies of two victims out of one burned building and a crowd of people looked on from the rubble-filled street as firefighters worked at the site.Hussein Ali, a 24-year-old former soldier, said six workers at his family's shop were killed in the attack, their bodies burned so badly that they could not be identified."I will return to the battlefront. At least there, I know the enemy so I can fight him. But here, I don't know who I'm fighting," Ali told AFP.ISIS issued a statement claiming responsibility for the suicide bombing, saying it was carried out by an Iraqi as part of the group's "ongoing security operations".'Cowardly and heinous act' The jihadist group said the blast targeted members of Iraq's Shi'ite Muslim majority, whom the Sunni extremists consider heretics and frequently attack in Baghdad and elsewhere.UN Iraq envoy Jan Kubich condemned the "cowardly and heinous act of unparallelled proportions," calling on authorities to bring those responsible to justice.Officials said another explosion in the Shaab area of northern Baghdad killed at least one person and wounded four on Sunday, but the cause of the blast was disputed.US National Security Council spokesperson Ned Price said the attacks "only strengthen our resolve to support Iraqi security forces as they continue to take back territory" from ISIS.Bombings in the capital have decreased since ISIS overran large areas north and west of Baghdad in June 2014, with the jihadists apparently occupied with operations elsewhere.But the group has struck back against Iraqi civilians after suffering military setbacks.A video posted on social media showed men - apparently angry at the government's failure to prevent the carnage in Karrada - throwing rocks towards what was said to be Abadi's convoy.A bystander could be heard cursing at Abadi in another video.In May, Baghdad was rocked by a series of blasts that killed more than 150 people in seven days.With thousands of vehicles moving in and out of the city each day, such bombings are difficult to prevent.But there are also flaws in Iraqi security measures in the city, especially the continued use of fake bomb detectors at checkpoints years after the man who sold them to Iraq was jailed for fraud in Britain.ISIS defeat in Fallujah Iraqi forces completely recaptured Fallujah, a city 50km west of Baghdad, from the jihadists a week ago.Anti-government fighters seized Fallujah in early 2014 and it later became one of ISIS's main strongholds in the country.ISIS's defeat there was compounded by a devastating series of air strikes targeting jihadist forces as they sought to flee the Fallujah area.Iraqi and US-led coalition aircraft destroyed hundreds of ISIS vehicles and killed dozens of fighters in two days of strikes against jihadist convoys after the end of the Fallujah battle, officials said.With Fallujah retaken, Iraqi forces are now setting their sights on second city Mosul, the last major population centre held by ISIS in Iraq.Initial operations aimed at setting the stage for a final assault on the city have begun, and the US-led coalition is carrying out strikes in the area.The Pentagon announced on Friday the coalition had killed two senior ISIS leaders in the Mosul area the previous week.In addition to Mosul, ISIS still holds significant territory in Nineveh province, of which it is the capital, as well as areas in Kirkuk to its west and Anbar to its south.The jihadist group seized control of large parts of Iraq and Syria in mid-2014, declaring an Islamic "caliphate", committing widespread atrocities and organising or inspiring a series of deadly attacks in Western cities and across the Middle East.