HATRA, Iraq - Hundreds of fleeing civilians clamber up the dusty banks of a wadi snaking through Iraq's Nineveh plains, gasping and pleading for help from Iraqi soldiers as explosions reverberate through the millennia-old town of Hatra behind them.

The elderly and sick are carried, a handful in wheelchairs are hauled up the sides of the wadi by young men. Soldiers and medics from the Hashd al-Shaabi (Popular Mobilisation Units), tasked with liberating the area from the Islamic State, rush forward into still hostile - and possibly mined - territory to help pull the civilians to safety.

We have literally escaped from death today because Daesh wanted to execute all of us - Samira, Hatra resident

Fear and hope merged on the sunburned faces of men, women and children, many of whom have spent days under the desert sun without food or fresh drinking water. Scrambling up the wadi banks, women begin weeping with relief and men gratefully embrace their saviours.

This is the scene outside Hatra, a town in northern Iraq whose story has been lost in the din of the battle for Mosul, but whose people have for three long years suffered all the same under the "caliphate" of Islamic State.

This week, their salvation grew nearer as Iraqi forces pressed an offensive to dislodge the hated occupiers.

"We had a terrible journey. We have literally escaped from death today because Daesh wanted to execute all of us," Samira, 59, told Middle East Eye.

"First they forced us to stay in tents on the outskirts of the town without food and then, at the last moment, took us back into Hatra to use as human shields."

Hashd al-Shaabi fighter helps children to safety (MEE/Tom Westcott)

She describes her terror as, just half an hour before Iraqi helicopters started bombing IS positions, armed militants told everyone to leave towards Iraq's Anbar province, the desert zone of which remains under IS control. And anyone who refused was to be shot.

When the air strikes started, IS militants were thrown into a state of confusion, and hundreds of civilians grabbed their chance to escape, Samira said, adding: "Even though Daesh were shooting at us as we fled, we knew this could be our only chance to escape."

Having endured nearly three years of barbarism under IS, reaching the wadi and seeing the Iraqi troops was their first taste of freedom.

We thought the world had forgotten about us - Fatima, Hatra resident

"After almost three years under Daesh, we had completely given up hope of either escape or rescue," Fatima, 39, told MEE. "We thought the world had forgotten about us."

She described miserable living conditions with very little food, no electricity, no access to healthcare and no communications.

"We completely lost contact with the outside world - no satellite dishes, no television and no telephones because everything was banned by Daesh - so we had no idea what was happening in the country, with politics or the army or anything," she said.

Smoke rises from IS targets in modern Hatra targeted by the Iraqi air force (MEE/Tom Westcott)

A few locals, however, had established secret communications with the Hashd al-Shaabi intelligence department and knew the forces were planning an attack.

"Daesh said the Hashd would kill us all and tried to force us to go to Anbar, but the Hashd had already promised us they were coming to save us, so most families tried to stay," said Falah, 43.

"I think Daesh took about 50 families, maybe more, to Saddam Hussein's old farms, which are on the way to the town of Housaba, in Anbar."

He added that a further few families had refused to leave their homes, particularly farmers who didn't want to leave their cattle - their sole livelihood - behind.

We are expecting stronger resistance when we reach Hatra itself but this will not stop us. - Kareem al-Hakakhi, Hashd al-Shabi commander

Iraqi forces launched a multi-pronged attack to liberate the historic city of Hatra, which nestles in the Nineveh plains 110km southwest of Mosul, on Tuesday.

Meeting only modest IS resistance of suicide car bombs and wayward mortars, within two days they had taken tens of kilometres of desert terrain, reaching the walls of the Old City and almost surrounding the town.

"We have met with very little resistance, mainly car bombs which our forces were able to destroy," Sheikh Kareem al-Hakakhi, commander of Hashd al-Shaabi's Second Division told MEE on one frontline on Wednesday.

"According to our intelligence, we are expecting stronger resistance when we reach Hatra itself but this will not stop us. We are not afraid of Daesh and we absolutely will take back Hatra."

Hashd al-Shaabi fighters advancing across the Ninevah plains towards the historic town of Hatra (MEE/Tom Westcott)

Hakakhi said intelligence reports showed IS had already been preparing to lose the town, starting to destroy some of their own headquarters and facilities in the town to eliminate evidence of their activities.

"Daesh destroy everything," he said. "And our intelligence suggests that they have also destroyed a lot of Hatra's historic Old City."

By the evening another Hashd al-Shaabi frontline had reached the Old City and on Thursday morning, under cover of heavy shelling, forces entered the modern town of Hatra, fighting through a limited IS defence of mortar bombs, snipers and machinegun fire.

Mosul: Countless dead and no one to help in relentless US bombing Read More »

One of Iraq's five Unesco world heritage sites, the ruins of the ancient fortified city of Hatra are believed to date back to the 2nd century BC and, before IS entered the town, were said to have been one of the best-preserved examples of a Parthian city.

IS militants started demolishing the site shortly after they seized control of Hatra in June 2014.

"Even though we haven't seen it, I'm afraid most of the old ruins have been destroyed," said 60-year-old Bilal. "After looting the site for all its precious antiquities to sell, Daesh blew up part of it and then took bulldozers in to flatten the rest.

"They said these historic things were forbidden by Islam, which is ridiculous."

An artefact destroyed by IS in Hatra's Old Town (Reuters)

Hindi, 47, said civilians and even ordinary IS fighters were forbidden to enter the ancient ruins.

"After Daesh came, they surrounded Old Hatra with armed fighters and used it as a headquarters for senior personnel," he said.

"Only very important, high-level members of Daesh were allowed to enter the site and, of course, no ordinary civilians like us.

"We could only see it from afar but it did look as if some of the ruins might have survived, maybe even 50 percent of it."

Since the Hashd al-Shaabi offensive started on Tuesday, Hindi said IS members had started fleeing towards Anbar, and estimated that only around 100 militants had remained to defend the town.

Our town suffered a lot through history, but we never endured anything so terrible as Daesh - Bilal, Hatra refugee

"Our town suffered a lot through history, but we never endured anything so terrible as Daesh," said Bilal, referring to repeated attacks by historic powers including the Ancient Romans and Persians.

"You can't even talk to these Daesh people, not even an older man like myself. Because the situation in Hatra was so terrible, I approached them several times and tried to reason with them but they are deaf to any opinion other than their own."

Abu Omar, 67, said Hatra's residents had been plunged back into Medieval times under IS.

"Our lives went backwards, literally centuries backwards, with no phones, cameras, televisions or modern things," he said.

"Imagine, we could not even make a phone call or take a photograph for almost three years."

He said, since mid-2014, IS rule had been characterised by a campaign of abductions and executions that kept residents in a state of fear and paralysis.

Shepherds herd their flocks of sheep into territory newly-liberated from IS (MEE/Tom Westcott)

"We could do nothing. We were completely powerless. "If we went to Daesh and asked about missing family members, we too would be arrested," he said.

"If you were caught with a telephone, you were executed immediately, especially recently because they became suspicious that people were communicating with the Iraqi forces."

As the Iraqi army helicopters circled over Hatra, bombing further IS targets, shepherds herded their unwilling flocks through the river towards the Hashd al-Shaabi bulldozers reinforcing the frontline with sand berms to protect the troops from incoming IS carbombs.

"If it was not for the Hashd and the Iraqi army reaching us today, I am sure we all would have been killed for refusing to go with Daesh to Anbar," said Hindi.

"All I want now is to go to a camp, with my family. I just want to get to a camp."

Hashd al-Shaabi fighters said Hatra's fleeing residents, which numbered more than 750 on Wednesday, would be transferred to purpose-built IDP camps in the town of Hamam Al-Alil, near Mosul.