Iraqi forces bolstered by coalition airstrikes have met with stiff resistance in the first step of their offensive to retake the Islamic State stronghold of Mosul.
About 4,000 Iraqi forces started their advance toward a number of villages about 75 kilometers southeast of Mosul at 6 a.m. Thursday. Pershmerga forces said some of the villages had been evacuated.
Reporting exclusively from the scene, VOA observed that the troops came from two directions, creating a pincer movement around the villages. By midafternoon, the troops had seized four villages, but had not yet managed to control all the area, Peshmerga General Najat Ali told VOA.
"They advanced, but when they reached those villages, IS attacked them with suicide bombers, by mortars, by machine guns, by those weapons," he said. "They [Iraqi forces] are now stopped; they cannot advance."
The forces are from two Iraqi brigades from Iraq's U.S.-trained 15th Division. Also involved are members of Sunni tribes, which many Peshmerga commanders have said are crucial to hold the traditionally Sunni areas.
WATCH: Iraqi Forces Start Offensive on IS Stronghold of Mosul
From the sandbagged berms of the front line, dark clouds of smoke in the distance rose from the horizon. Peshmerga soldiers said IS had set tires on fire to create clouds of dark smoke in an attempt to obscure their positions.
But as Najat Ali and his forces paid close attention, looking through binoculars, coalition airplanes flew overhead and pounded one of the villages with airstrikes.
U.S. officials said coalition aircraft launched multiple airstrikes on at least two locations.
WATCH: Video footage from the scene
In addition, 200 U.S. Marines were operating out of a small outpost called Fire Base Bell to provide artillery and targeting support for Iraqi forces.
Najat Ali said the fight was a pivotal moment.
"Now, really indeed, if the Iraqi army succeeds in this operation, they will succeed in the second and third step to liberate Qarrayah and Mosul," he said. "But if they fail in the first step, they will fail to liberate Mosul. They will not liberate Mosul easy; maybe it is harder than before."
Another Peshmerga commander located to the north of Mosul said the area the Iraqi army was fighting for included roads connecting Mosul to other Iraqi cities, as well as the Qayyarah bridge across the Tigris river.
“They are trying to clear this area because it is important,” Peshmerga General Hussein Nooraldin told VOA.
When night falls ...
As it got later in the warm, spring afternoon, Najat Ali said it was crucial for the Iraqi forces to decide whether to retreat or press on.
"When it is becoming night, maybe it's a problem for the Iraqi army," the Peshmerga general said. He said his forces were bracing for a possible IS counterattack.
Both Kurdish and Iraqi flags flew from the small front-line post, but the Kurdish Peshmerga are not taking an active part in the fight. They are holding the front line at what they consider the border of Kurdish territory.
Yet parked directly behind them were mobile and field artillery.
The offensive was launched from Makhmour, where a U.S. Marine was recently killed in an IS rocket attack. Iraqi forces have been gathering in the area in recent weeks.