Iraqi Prime Minister Haider al-Abadi formally declared victory over Islamic State in the city of Mosul on Monday, marking the biggest defeat for the group since it declared a caliphate three years ago.
“I announce from here the end and the failure and the collapse of the terrorist state of falsehood and terrorism which the terrorist Daesh announced from Mosul,” he said in a speech shown on state television, using an Arabic acronym for Islamic State.
The U.S.-led coalition backing Iraqi forces welcomed the victory but warned it did not mark the end of its global threat and urged Iraqis to unite to defeat the militants.
“While there are still areas of the Old City of Mosul that must be back-cleared of explosive devices and possible ISIS fighters in hiding, the ISF [Iraqi security forces] have Mosul now firmly under their control,” it said in a statement.
The fall of Mosul effectively marks the end of the Iraqi half of the Islamic State caliphate, which also includes territory in Syria. The group still controls territory west and south of the city.
A 100,000-strong coalition of Iraqi government units, Kurdish Peshmerga fighters and Shia militias launched the offensive to recapture the city from the militants in October, with key air and ground support from the U.S.-led coalition.
Abadi, wearing a black military uniform and flanked by commanders from the security forces, thanked troops and the coalition. He also warned that more challenges lay ahead.
“We have another mission ahead of us, to create stability, to build and clear Daesh cells and that requires an intelligence and security effort, and the unity which enabled us to fight Daesh,” he said before raising an Iraqi flag.
About 900,000 residents have been displaced by the fighting, and thousands of civilians are believed to have been killed.
In the aftermath of victory, Abadi’s government now faces the task of managing the sectarian tensions in Mosul and elsewhere that enabled Islamic State to win support, and the threat of a wave of revenge violence in the city.
Islamic State leader Abu Bakr Baghdadi has fled the city and his whereabouts are unknown. Reports have circulated that he is dead but Iraqi and Western officials say they cannot corroborate this.
His death or capture would not be the end of Islamic State, which still controls areas south and west of Mosul and which is now expected to take to the desert or mountains to wage an insurgency.
The militants are expected to keep trying to launch attacks on the West and inspiring violence by “lone wolves” or small groups of the kind mounted recently in Britain, France and elsewhere.
But the loss of Iraq’s second-largest city is a grave body blow to Islamic State.
“The recovery of Mosul is a significant step in the fight against terrorism and violent extremism,” said the spokesman for UN Secretary-General Antonio Guterres.
Jaafar Sadiq, a member of Iraq’s counter-terrorism force, said military operations had been completed in Mosul’s Old City, which saw heavy fighting in recent weeks as the Islamists made their last stand.
Islamic State is also under heavy pressure in its operational headquarters in the Syrian city of Raqqa.
The stench of corpses along Mosul’s streets was a reminder of the gruelling urban warfare required to dislodge Islamic State. Much of the city of 1.5 million has been destroyed in the fighting, its centuries-old stone buildings flattened by air strikes and other explosions. One of Islamic State’s last acts was to blow up the historic al-Nuri mosque and its famous leaning minaret.
“It’s a relief to know that the military campaign in Mosul is ending. The fighting may be over, but the humanitarian crisis is not,” said UN Humanitarian Coordinator for Iraq Lise Grande.
“Many of the people who have fled have lost everything. They need shelter, food, health care, water, sanitation and emergency kits. The levels of trauma we are seeing are some of the highest anywhere. What people have experienced is nearly unimaginable.”
Iraqi soldiers relaxed. Some swam in the Tigris river which runs through the city. One wiped the sweat from his face with an Islamic State flag.