Irbil, Iraq (CNN) The small dorm room in Kirkuk, with gray-speckled terrazzo floors and wooden cots, was home to Monaly Najeeb and six other Christian women after ISIS took hold in Mosul and they were forced to abandon college.

They restarted their studies in the Kurdish-controlled city, in that humble room, where they could once again study, pray and even laugh.

The church-run residence for the displaced girls became a sanctuary.

Until one terrifying day last week.

The horror began early on Friday, before the sun had a chance to rise. Monaly, an engineering graduate who became a mentor to the other women, spoke through an interpreter to give this account to CNN.

The girls hid in this room for seven hours until ISIS fighters finally left.

It was about 4 a.m. when the women heard gunfire and explosions outside. Five days earlier, Iraqi and Kurdish Peshmerga forces had launched a major offensive to oust ISIS fighters in Mosul. Now Kirkuk , 100 miles to the south, had become a target for retaliation.

The women knew the wrath of the ISIS militants who overtook their university in Mosul, burned thousands of books and demanded the curriculum adhere to their own harsh interpretations of Islam. The girls' families lost ancestral homes in Qaraqosh, once Iraq's largest Christian city, when they fled to survive.

Now, in their dorm room, they would again have to fight for survival. But this time, they would do it not by fleeing but by staying put.

Monaly and her friends wrapped themselves in blankets to protect them from flying bullets. Soon, they heard muffled voices in the kitchen next door and the sound of people opening the refrigerator and rummaging through cabinets.

Monaly Najeeb stayed in touch by text with a young priest her phone died.

The women dove under their flimsy wooden cots. They couldn't tell if the intruders were Iraqi military or ISIS. Monaly wanted to yell out for help. But if she took that risk and was wrong about the strangers' identities, she and her friends were certain to die.

So instead she lay perfectly still, not even wanting to breathe, hoping everyone's phones were in silent mode. She held in her need to relieve herself. One woman had severe allergies; if she coughed or sneezed, it could be over.

Monaly clutched a clear glass rosary and prayed.

"Father, help us," she texted Father Roni Momika, a young priest in Erbil who ministers to displaced Christians. "Are you in contact with the army?"

"Pray to the Virgin Mary," he assured her. "She will protect you."

The girls cowered in fright as the men left the kitchen and entered their bedroom. They could tell from their conversations that they were ISIS fighters.

The militants sat on the beds and ate. They ruffled through the girls' bags and found their clothes. Monaly grew more nervous. She'd read about the horrific abuses ISIS inflicted on women. The beatings, rapes and forced enslavements. Now the intruders in their house knew women were living here.

Monaly did not fear death as much as rape. She trembled at the thought of being overpowered by men she loathed.

Outside, in Kirkuk, the fighting raged. With the help of sleeper cells, infiltrating ISIS combatants locked into heavy gun battles with Iraqi forces and attempted to capture key buildings.

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The militants brought their injured into the building; one man was moved into the dorm room. The fighters laid their comrade on a cot. Blood soaked through the mattress and dripped onto Monaly's friend hiding underneath.

Still, not one woman moved. Or made a sound.

An ISIS fighter grabbed a blanket for the injured man. He could easily have chosen the blanket shielding Monaly; instead he chose another. Two men sat right above her, so close that she could feel one man's shoes touching her.

More than seven hours passed. One by one, the batteries died on the women's cell phones, their only link to the outside world extinguished.

Security teams arrive on the scene of an ISIS attack in Kirkuk last week.

"They will kill us," Monaly wrote in her last text to Father Momika. Then, her phone went black.

Momika feared the women were dead. In Erbil, his phone in hand, he began to cry.

But one phone had refused to drain. Through it, the women would receive instructions on how to escape.

When the men in the dorm room got a phone call telling them to leave, the women prepared to follow. But Monaly could hear water running in the bathroom and knew ISIS fighters were still in the house. Quietly, she and the others crawled out from under the cots and did as they'd been told by Iraqi police: They ran out the back door and toward an 8-foot wall. Monaly led the way.

Iraqi Kurdish security forces detain a suspected ISIS fighter in Kirkuk on October 22.

By chance, a chair sat in front of the wall. The women used it to climb over.

Later, militants detonated their suicide vests. Monaly saw their remains when she returned the next day.

She recounted this story on a quiet evening at the house her family calls home in Erbil. As she talked, she clutched the white glass rosary.

"I don't know how we stayed alive," she said.

I don't know how we stayed alive. Monaly Najeeb

An officer with the security police in Kirkuk, Anwar Omer Rasool, confirmed to CNN that the women had been trapped in their dormitory during the ISIS attack on the city.

Monaly and her friends felt they were saved by a series of miracles.

No one coughed or sneezed. No one's phone pinged. A solitary chair sat in front of that high wall, where normally there was none.

At times during the ordeal, Monaly lost hope. But her faith grew stronger.

Initially, she agreed to tell her story only if CNN would not use her real name. But she changed her mind. She is ready, she said, for the world to know who she is and what she endured.

Ready, she says, because she survived ISIS. And she has nothing left to fear.