Transcript for US Supports Iraqi Forces in Mosul
Now overseas to the fight against ISIS, the U.S. Is lending support to a massive military operation now in its second day. To knock the terror group out of its last stronghold in Iraq and Alex Marquardt has more from the front lines. He's at a refugee camp. Reporter: Progress is being made but it's slow going. ISIS showing they are not going away without a fight. We are here at a camp for the displaced. Many lived under ISIS and been telling us their stories as the U.N. Braces for a huge new wave of people fleeing the fighting. Pushing towards mosul, Iraqi forces this morning on the move, here fighters going house to house to take back a village. But the militants putting up fierce resistance, booby trapping hopes and sending out suicide many Boers. Air strikes from the U.S. Led coalition have paved the way. American special forces are advising the troops. Leaflets dropped telling residents to stay inside away from ISIS positions. Here a truck careening into a line of Iraq tanks then exploding. ISIS claimed it deploys 12 suicide bombers on the first day of fighting. Aid agencies are bracing for hundreds of thousands fleeing. Many have lived under the terror of ISIS, hussein telling us he and his brothers were due to be executed with 250 others for resisting before they escaped. Reporter: You can't sleep without fear? Yes, you cannot guess when will they take you at night. Reporter: They would just come and randomly come and take people and kill them. We will hear a lot of stories like that in the coming days. It could be sometime before it is over. It could be weeks or months before ISIS is pushed out of mosul.
This transcript has been automatically generated and may not be 100% accurate.