BAGHDAD — Iraqi forces have seized most of Mosul’s airport, an important milestone in the broader offensive to retake from the Islamic State the western half of the city, allied and Iraqi officials said on Thursday.
The push to take the airport, which has been spearheaded by the Iraqi Federal Police, is a promising start for what is expected to be a difficult and bloody fight to evict the group from the city, the country’s second largest.
“They are most of the way through the airfield,” said Brig. Gen. Matt Isler, a senior United States Air Force officer in the American-led coalition.
It took Iraqi forces 100 days to seize the eastern half of the city, an operation that led to significant Iraqi casualties. Gen. Joseph L. Votel, the head of the United States Central Command who arrived in Baghdad on Thursday, said that about 500 Iraqi military personnel were killed and about 3,000 wounded in that operation.
After taking the eastern portion of the city in recent weeks, Iraqi forces paused to strategize about how to best reclaim the western half.
One decision was to resume their offensive and take the rest of the city on multiple axes so that the Islamic State would find it difficult to coordinate its defenses.
The new Iraqi offensive was proceeded by a powerful series of airstrikes against 33 targets, including headquarters where commanders from the Islamic State, also known as ISIS or ISIL, were believed to be operating. The group first conquered the city in 2014, but has consistently lost ground to Iraqi forces backed by coalition air support.
One bombing attack was directed at a five-story medical center in west Mosul that an American official said had been turned into an ISIS command center. Militants often use hospitals, schools and religious buildings, in the hopes that coalition forces would be reluctant to bomb them. In this instance, American officials said they determined that no civilians were present.
Iraqi forces have been attacking with a three-pronged approach. Moving south to north, Iraq’s Federal Police took Abu Saif, a town that sits on high ground overseeing much of Mosul, before moving on to the airport.
Iraq’s counterterrorism service, the premier fighting force in the country, has been moving along the west toward Ghazlani. All 14 of the counterterrorism service’s fighting battalions have been committed to the Mosul fight.
Still further west is the Iraqi Army’s Ninth Division, a tank unit.
American and allied planes, including F-15E “Strike Eagles,” AV-8B Harriers and French warplanes have provided close air support for the Iraqis. American Army Apache attack helicopters have also fired Hellfire missiles to help the Iraqis advance.
Shiite militias, officially known as the Popular Mobilization Forces, have moved to cut off the routes to Mosul and are operating west of the city. The Americans have not been carrying out airstrikes to support these fighters, many of whom are backed by Iran. Instead, the Iraqi Air Force has been carrying out airstrikes in this area.
The battle for western Mosul is expected to be difficult, given the city’s many narrow and winding streets, in which armored vehicles cannot maneuver. Much of the fighting will need to be done by Iraqi troops fighting house to house.
The precise number of ISIS fighters in Mosul is not clear, though some military officials estimated there are 4,000 to 6,000 militants there.