Iraqi Forces Enter Mosul After 2-Week Offensive, Heavy Fighting Commanders have said the battle for Mosul could take months.

 -- In a fresh assault on the ISIS stronghold of Mosul, Iraqi special forces fought their way into the city at daybreak this morning under heavy fire. Iraqi special forces commander, Abdul Ghani al Assadi tells ABC News his troops have entered the city limits and are fighting to isolate the eastern neighborhood of Gagjali.

ISIS car bombers are reportedly trying to stop the advance. The assault saw armored vehicles, including heavy tanks, move on the suburb of Bazwaya and then onward into the city as allied artillery and airstrikes hit ISIS positions, drawing mortar and small arms fire.

Several prongs of forces allied with the Iraqi government have been fighting their way through the towns and villages that surround Mosul in the two weeks since the offensive began.

Iraqi Federal Police and People’s Mobilization Units (PMU) Shia militias have taken control of the town of Jurn, on the southern approach to Mosul, just ten miles from the border of the city.

Shia militia commanders say it’s all going well in their fight to take Tal Afar, to the west of Mosul, yet a pro-Turkish government newspaper says it would take a very long time for Iran-backed Hashd al-Shaabi (PMU) forces to beat ISIS in Tal Afar. Turkish military sources told the newspaper the Shia groups are not near the town and claim their reports are part of a psychological warfare attempt.

There are as many as 5,000 ISIS fighters inside Mosul, in addition to up to 2,500 guarding the city's outer perimeter, according to U.S. military estimates.

The Iraqi forces have also added a key piece of infrastructure to their effort. An Iraqi Air Force C-130 transport plane landed at Qayyarah West Airfield Sunday for the first time since it was recaptured from ISIS and repaired by coalition engineers. The airfield will now be able to serve as a base for launching air assaults and support during the fight to liberate Mosul and operations throughout the rest of northern Iraq and Syria.

As the fighting pushes into the city, the danger to civilians in densely-populated areas may increase, international aid groups say. Save the Children warned that as many as 20,000 children could be among the civilians reportedly being held by ISIS within the city as human shields.

"There are around 600,000 children in Mosul and their families are being forced to choose between staying, and facing a multitude of dangers including being used as human shields, or fleeing and running a gauntlet of fighters, snipers and landmines," the group said in a statement.

According to aid workers at the International Organization for Migration, more than 18,258 people have already been driven from their homes as a result of the military conflict in Mosul.

The Associated Press contributed to this report.