The Pentagon on Monday welcomed the recapture of the Iraqi city of Fallujah from the Islamic State group, but warned of widespread booby traps and pockets of remaining militant resistance.
Iraqi forces seized the IS group's last positions in Fallujah on Sunday, establishing full control over one of the militants' most emblematic bastions after a month-long operation.
"The United States military and our coalition partners are proud to have supported the Iraqi Security Forces under the prime minister's command in this important operation," Pentagon chief Ashton Carter said in a statement congratulating Iraq Prime Minister Haider al-Abadi.
Iraqi forces will likely continue to meet pockets of resistance and have much dangerous work ahead as they clear homemade bombs -- known as IEDs -- from the city, officials cautioned.
"Not just vehicle-borne IEDs but these house-borne IEDs which are particularly nasty to try to clear," said Pentagon spokesman Captain Jeff Davis.
Carter added it was important the Iraqi government investigates alleged human rights abuses carried out by security forces against some civilians as they tried to flee the city.
The US-led anti-IS coalition's focus now shifts north, where the ultimate goal is to recapture Mosul, the militants' main Iraq stronghold.
The coalition is helping Iraqi troops move north from Baiji towards the town of Qayyarah, which lies around 35 miles (60 kilometers) south of Mosul on the banks of the Tigris river.
Abadi had already declared victory in Fallujah on June 17 after IS group defenses collapsed, with Iraqi forces facing only limited resistance in subsequent clearing operations.
The fighting to get into Fallujah was initially fierce, particularly on the southern side, and Iraqi forces were supported by more than 100 US-led coalition air strikes.
"To some extent once (Iraqi troops) got through the hard candy shell and into the chewy center, things went much more quickly," Davis said.
"It was really a heavy fight along the frontline but once they penetrated in it seemed to go very quickly."
Davis said the recapture of Fallujah would "significantly" help the security situation in Baghdad, where IS group fighters thought to have come from Fallujah have carried out a string of bomb attacks in recent weeks.
"The loss of Fallujah will further deny ISIL access to a province that is critically important to its overall goals," he said.