They were ISIS human shields in Mosul. Now they tell how they broke free.

MOSUL, Iraq — When Zahra Atiya tried to leave her house to get some clean water last month, black-clad Islamic State fighters ordered her back inside. Her family cowered in their house and abandoned any thought of escape when they peered through their windows and saw the militants execute people on the street.

"They wanted to protect themselves behind the people," said Atiya, 52, one of the lucky captives who managed to escape.

Atiya is one of a dozen residents USA TODAY interviewed about their harrowing experience as human shields while waiting for Iraqi forces to liberate them from a diminishing band of ruthless militants who appear determined to fight to the death.

On Sunday, Iraqi Prime Minister Haider al-Abadi celebrated with his troops in Mosul, congratulating them for their victory over the Islamic State, although some fighting continues with the last remnants of the militants in the city.   

Residents described how they had been confined to their homes without food or clean water, experiencing a mix of dread and desperate hope that they would be able to break free.

"When it was quiet, we were scared," said Atiya. "But when we heard the noise of gunfire and bombs, we were telling each other: 'The army is coming, they're going to get us out of here."

Atiya and her five family members managed to flee into the safety of Iraqi special forces on Thursday. She described how the militants knocked a big hole in the wall of their house and moved through it every few days, and often headed to the roof of a nearby schoolhouse, the only building on the block over one-story high.

The Islamic State, also known as ISIS, has used civilians as human shields during its three-year occupation of northern Iraq, but there was a "significant escalation" of the practice in June, according to a United Nations refugee agency report.

The agency said that on a weekly basis for the past several months, ISIS fighters indiscriminately shot or beat to death hundreds of civilians who tried to escape.

Hundreds more were killed each month in airstrikes by a U.S.-led coalition, as ISIS fighters targeted by the bombing campaign surrounded themselves with civilians, according to estimates by the British watchdog organization Airwars.

Civilians with homes taller than one story said ISIS fighters used their roofs to set up mortar or sniper emplacements. USA TODAY saw a half-dozen abandoned mortar launchers and piles of shells in several residences near Mosul's Old City.

"(The Islamic State) chose strategic houses with the most civilians in them," said Foad Dawod, 22, who had been stuck in one such house before he was wounded in an airstrike. He managed to escape and make his way to Irbil, about 50 miles to the east.

Abd al Razzak Ahmed, who was fleeing Mosul with his family on Thursday, said they were stuck inside their house for days at a time while ISIS fighters set up on their roof and blasted away at Iraqi troops. The fighters fled through a hole in the wall shortly before an airstrike or rocket explosion collapsed the house atop Ahmed's daughter, killing her. The rest of the family managed to escape into liberated territory.

While trapped, he said, it was impossible to go out and replenish their food supplies or get clean water, making his family weak and afflicted with gastric illnesses, a common complaint of several escapees.

The families said they could not flee until Iraqi forces reached them because ISIS fighters were all too willing to fulfill their threats of killing anyone who tried to escape.

Zikra Mohammed, 33, who made it to a refugee camp on Wednesday, said the militants caught her family in the street after her first escape attempt, accused her of "going into the land of the infidels" and forced her and her family back to their house.

"We tried to tell them we are not infidels, we are just hungry and tired and my children need to see a doctor," Mohammed recounted. The ISIS fighters grabbed her 18-year-old son, the oldest male in the house at the time, and savagely beat him with big sticks. Without medical attention, the boy died from his injuries, she said.

Iraqi soldiers confirmed they saw ISIS fighters shoot civilians. Commander Mohammed Tariq Ali of the Iraqi army's 16th Division said that during his troops' assault on a neighborhood outside the Old City, his men saw a mother holding a baby cut down by gunfire coming from ISIS positions. The militants then killed one of the soldiers trying to retrieve the baby from the battlefield. The child survived but the mother did not, he said.

More than 875,000 people fled Mosul since the battle to liberate Iraq's second largest city began in October, according to the U.N. refugee agency.

Estimates of remaining civilians vary. The U.N. said tens of thousands remained through June, but Iraqi forces said only several hundred to several thousand are still there. USA TODAY observed largely empty streets in and around the Old City, as well as hundreds walking out of recently recaptured neighborhoods to be trucked to the refugee camp.

Those held as human shields are still traumatized but cling to their newfound freedom to keep their spirits up. "I am 52 years old," Atiya said. "But when I escaped, I felt young again. We are finally free."

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