BAGHDAD — As celebrations for the Muslim holy month of Ramadanstretched past midnight into Sunday in central Baghdad, where Iraqis had gathered to eat, shop and just be together, a minivan packed with explosives blew up and killed at least 143 people — the third mass slaughter across three countries in less than a week.
The attack was the deadliest in Baghdad in many years — at least since 2009 — and was among the worst Iraq has faced since the American invasion of 2003. The bombing came barely a week after Iraqi security forces, backed by American airstrikes, celebrated the liberation of Fallujafrom the Islamic State, which almost immediately claimed responsibility for the attack.
Even as fires still blazed Sunday morning at the bombing site, Iraq’s machinery of grief was fully in motion: Hospitals tried to identify charred bodies, workers sorted through the rubble searching for more victims, and the first coffins were on their way to the holy city of Najaf and its vast cemetery, always expanding, where Iraq’s Shiites bury their dead. By Sunday evening, a worker at the cemetery said more than 70 bodies had arrived, and many more were expected on Monday.
There were also immediate political repercussions, as the bombing brought an abrupt end to the brief victory lap that Iraq’s beleaguered prime minister, Haider al-Abadi, was enjoying after the recapture of Falluja. Mr. Abadi rose to power in 2014, and the Obama administration had hoped that he could reunite the country after the divisive tenure of his immediate predecessor, Nuri Kamal al-Maliki, whose sectarian policies were blamed for the rise of the Islamic State.
Given the anger swelling in the streets of the capital, many are now sure to wonder how long Mr. Abadi may remain in power; at the very least, the chaos is likely to presage the resumption of street unrest that had calmed during Ramadan and the military operations in Falluja.
The scenes that unfolded across the city on Sunday were another brutal illustration of the paradox Iraq faces as its security forces — and the American military, which is training the Iraqi Army and carrying out airstrikes and raids by Special Forces — make gains against the Islamic State. As more territory is won back, the group is reverting to its roots as a guerrilla insurgency, turning Baghdad again into an urban killing field.
Assaults like the one early on Sunday, as well as a string of attacks in Baghdad in May that killed more than 200 people in a week, make it difficult, if not impossible, for Mr. Abadi, a Shiite, to make meaningful progress in reconciling Iraq’s majority Shiites with Sunnis.
But the ferocity of the attack, and the ease in which the Islamic State is able to carry out mass murder in Baghdad, demonstrate another monumental challenge if the extremist group is driven from areas under its control: Not only will reconciliation be paramount, but any lasting peace will also require a lengthy counterinsurgency campaign that will challenge the Iraqi security forces and, perhaps, require a deepening involvement by United States forces.
When Mr. Abadi visited the bombing site on Sunday morning, people threw rocks and shoes — a particular insult in the Arab world — at his convoy and yelled, “Thief,” an epithet directed as much at Iraq’s dysfunctional and corrupt political class as it was to the prime minister personally.
Mr. Abadi was forced to quickly leave with his bodyguards. Later, he issued a statement saying that it was his “moral duty” to visit the site of terror attacks, and that he understood “the feelings and emotions and the actions of some people in their moment of sadness and anger.” He also declared three days of national mourning for the bombing victims.
He said the attacks were an attempt by the Islamic State to erase the jubilation many Iraqis felt about the liberation of Falluja. “I ask that God enable us to defeat terrorism and to protect our people, to have mercy on the martyrs and quickly heal the wounded, and to unite the Iraqis and crown their sacrifices with great victory,” he said.
The bombing occurred in the middle-class neighborhood of Karada, a busy district of cafes, shops and hotels, not to mention Mr. Abadi’s childhood home, as Iraqis joyously marked Eid al-Fitr, the days-long post-Ramadan festivity.
Many of the victims were children; the explosives detonated near a three-story complex of restaurants and shops where families were celebrating a successful end of the school year, residents said.
On Sunday afternoon, dozens of people were still unaccounted for. One man, Omar Adil, said two of his brothers, Ghaith and Mustafa, were missing. Five people from a single family in Sadr City, a poor Shiite neighborhood in eastern Baghdad, were also missing.
Ali Ahmed, 25, who owns a shop close to where the bomb went off, said that in the aftermath, knowing how many children were inside a shopping mall that was hit, he began yelling: “The kids upstairs! The kids upstairs! Save them!”
“But the firefighters arrived too late,” Mr. Ahmed said.
Later, he helped carry the bodies of children out of the rubble. He voiced anger at the security forces for failing to stop the bomber, and questioned why the street, which had been closed off earlier in the evening, was reopened around midnight.
“Thank God I managed to hit Abadi with stones to take revenge for the kids,” he said.
The Sunni extremists of the Islamic State, also known as ISIS or ISIL, almost immediately claimed responsibility for the attack, saying it was the work of a suicide bomber and had killed a gathering of Shiite Muslims. But Karada is a mixed area where Iraqis of all identities gather to do ordinary things — mainly to shop and eat — and many Sunnis were killed, too.
Abdulkareem Hadi, a shop owner in Karada, said that late Saturday he had to go home briefly, and asked two of his friends to watch his store. On Sunday morning, he was mourning those friends, Saif and Abdullah, who both owned clothing stores near his.
“I could not recognize their bodies,” he said. “ISIS says, ‘We kill Shiites,’ but I lost my dearest friends to me in this explosion, and they were Sunnis.”
Late last week, the Islamic State took responsibility for an attack at a restaurant in Dhaka, Bangladesh, that left 20 people dead, some of them hacked apart by swords and knives. And a few days before that, a coordinated suicide attack on Istanbul’s main airport killed more than 40 people. The Turkish authorities have blamed the Islamic State, although the terrorist group has not claimed responsibility.
Officials said on Sunday night that the death toll in Baghdad stood at 143, and that at least 195 were wounded. But that tally may well grow in the days ahead, given that many people were still unaccounted for and that many of the wounded were in critical condition. Hospital officials, accustomed to the gory aftermath of terror attacks, were horrified, saying they had never seen so many charred bodies, and that many of them could not be identified.
Abdullabas Ameen, an Iraqi Navy officer from a rural area of southern Iraq, was a patient in one of the hospitals, with shrapnel wounds to his chest and thigh. He came to Baghdad for a military course, and said he had been in a great mood Saturday night, enjoying the cosmopolitanism of the capital, and shopping for Eid.
“Those feelings didn’t last for long,” he said. “Suddenly I felt an earthquake, and a huge explosion. I felt myself in the middle of smoke, fire, destruction and screaming.”
He said he had lost a colleague, and then railed against the government for failing to protect its citizens. “The government is completely responsible for this daily bloodshed,” he said.
In the weeks ahead, as Iraqis face soaring summer temperatures, a lack of electricity to power air-conditioners and growing anger over security lapses, many expect a return of street protests.
Beginning last summer, a street protest movement gathered steam, demanding that Mr. Abadi root out corruption, end the system of handing out government posts based on sect and improve services. He made several proposals but has been unable to make meaningful changes in the face of opposition from other political blocs worried about losing their influence.
The protest movement ebbed and flowed over months, and at various times different factions sought to capitalize on the growing fury of Iraq’s citizens. This year, the powerful Shiite cleric Moktada al-Sadr, who commands a following among millions of the country’s Shiite underclass, tried to seize the movement, and twice his followers stormed Baghdad’s fortified Green Zone, the citadel of government.
But in their grief on Sunday, the political fallout was far from many Iraqis’ minds.
At the bombing site on Sunday, a woman, who had lost her husband and whose two sons were among the missing, was too grief-stricken to leave the scene.
All she could say was, “I don’t want to go to Najaf.”