WASHINGTON - U.S.-backed forces battling the last remnant of the Islamic State's self-declared caliphate penetrated deeper into the terror group's enclave Thursday, resulting in the second mass surrender in almost as many days.
Fighting on the outskirts of the northeastern Syrian town of Baghuz has been intense, with coalition airstrikes and artillery rounds lighting up the night sky while IS fighters launched several waves of suicide bombers at the advancing Syrian Democratic Forces.
But as the sun rose Thursday, hundreds of men, women and children began making their way out of the caves and tunnels, which had served as their last refuge.
Many men walked gingerly, their bandages clearly visible. Some mothers, holding their young children, stumbled as they made their way down from a rocky outcrop while the sounds of the occasional mortar round or gunshot could be heard in the background.
Officials said, in the end, 1,300 people surrendered to SDF forces Thursday, bringing the total number of people to leave Baghuz since the SDF resumed its final assault Sunday to more than 4,000.
SDF and U.S. officials said the continued evacuations have slowed the latest offensive, though progress is being made, with forces using multiple axes to penetrate deeper into what had been IS-held territory.
SDF officials said at least 112 IS fighters have been killed since Sunday, though they don't know how many more remain.
"Daesh militants can see us, but we can't see them or their movements during the daylight," SDF spokesman Mustafa Bali told VOA, using the Arabic acronym for the terror group.
U.S. defense officials have likewise said that the terror group's use of caves and tunnels have made it difficult to estimate just how many people remain entrenched in the shrinking sliver of land the terror group calls its own.
Both SDF and U.S. military officials remain optimistic it is only a matter of time before all of Baghuz is liberated from IS control. Still, some additional help has been brought in.
Sources close to SDF leadership tell VOA Kurdish special forces from Iraq, boasting advanced U.S. weaponry and training, have been transported to Baghuz to aid in the fight.
But despite added SDF firepower and a continual bombardment by both coalition aircraft and artillery positions on the ground, at least some of the terror group's fighters have refused to give in.
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In an audio recording posted online Sunday, an IS fighter claiming to be in Baghuz called on other followers to find inspiration in the fight and take action.
"My brothers in Europe and in the whole world ... be fierce and hard on the crusaders," the fighter said, according to a translation by the SITE Intelligence Group. "Kill them and displace them in revenge for your religion and your dignity."
In a separate video, another fighter says death would be a "victory" for the last of the IS defenders as they never lost their faith.
The SDF launched its final assault on the IS enclave late Sunday after pausing operations for nearly a week to allow more than 20,000 civilians, many related to IS fighters, to evacuate Baghuz for displaced persons camps. Hundreds of fighters also surrendered. Many of the IS fighters and families leaving now and surrendering are not Syrian.
The commander of U.S. forces in the Middle East, General Joseph Votel, warned U.S. lawmakers last week the evacuations were not a surrender, but a "calculated decision" and part of a strategy to allow the terror group to complete its transition to a clandestine insurgency.
Despite losing administrative control over almost all the land it once held in Syria and Iraq, U.S. defense officials caution IS still has "tens of thousands" of fighters working either as part of sleeper cells or as part of an active, clandestine insurgency.