ERBIL, Iraq (Reuters) - A medic peeled blood-soaked bandages from the arm of a boy in the emergency room of a hospital in northern Iraq, revealing the full extent of the damage inflicted by an Islamic State mortar attack.

Displaced people who were injured in clashes and fled from Islamic State militants in Mosul, receive treatment at a hospital west of Erbil, Iraq, November 25, 2016. REUTERS/Azad Lashkari

“Is something wrong with my hand?” the boy asked his father, who stood over the stretcher covering his son’s eyes to prevent him seeing the wound.

“It’s nothing, just a small wound,” replied the father, Abu Nidal, as the medic inspected the mangled remains of the boy’s hand, maimed beyond repair.

Around them were dozens of other civilians who have been wounded in areas of Mosul since they were retaken from Islamic State by Iraqi forces trying to dislodge the militants from their largest urban stronghold in Iraq.

The civilians say are not accidental victims caught in the crossfire and that Islamic State has been targeting them.

“In any area liberated by the army, Daesh (Islamic State)considers us apostates, so it is permissible to kill us,” said the boy’s father, who asked not to be identified.

His son had insisted on accompanying him to buy flour at a market in the Zahra neighborhood of Mosul when a mortar bomb hit them, nearly three weeks after Iraqi forces entered the district.

As Iraqi forces edge forward in Mosul’s eastern districts, taking pains to avoid harming civilians, Islamic State mortar and sniper fire is hitting the people it ruled harshly for more than two years.

With more than 100,000 men backed by an international coalition arrayed against an estimated 5,000 to 6,000 insurgents inside the city, there is little doubt Iraqi forces will eventually prevail. The question is at what cost.

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PRICE OF FREEDOM

An average of 100 casualties are arriving each day at the hospital in the Kurdish regional capital Erbil, where those with wounds too serious to be treated at field clinics on Mosul’s outskirts are rushed, a hospital administrator said.

In the burns unit, a 28-year old woman lay wrapped in bandages, only part of her face showing. Ten days after the army retook her neighborhood, she was making bread when her stove was knocked over during a mortar attack and she was set ablaze.

“They (Islamic State) harmed us after the liberation,” she said in a weak voice.

About 70,000 of Mosul’s estimated population of 1 million have fled to camps in the surrounding area, according to U.N. figures, but the majority have remained in their homes.

“We decided to stay because my mother and father are ill and it’s hard to live in a camp,” said 42-year old Abu Abd al-Rahman. That decision cost him a leg, he said, folding back a blanket to show a stump below the knee.

“May God take revenge on them,” he said.

Despite the growing number of casualties, the wounded praised the conduct of the Iraqi security forces and said it was a price worth paying to be free again from Islamic State.

“We are happy to be liberated, but Daesh spoiled it,” said 38-year-old Abu Ahmed, a blanket covering a leg wound after he was shot by a sniper. “They have no mercy”.

Across the corridor was Ziyad Younis, who buried his elder brother en route to the hospital. He is now tending to a nephew wounded in a mortar attack as he had breakfast.

“Our one hope was to be liberated; we didn’t expect it to be like this,” he said.