MOSUL, Iraq (WASHINGTON POST) - Aya Abosh found her sister in the house where she spent her final moments, trapped with her boys as shells fell from the sky and caved in the roof.

They were lying there, in the detritus of floral blankets and twisted railings. "Hammoudi," Abosh said, somehow recognising her six-year-old nephew Mahmoud. Recovery workers toiled around her, struggling to find a zipper on a body bag, then straining to wrap remains disfigured by trauma, time and sun.

Sajjida, her sister, was 28 and devoted to God, Abosh said. Bakr, the other boy, was nine. In the heat, stench and swirling dust, Abosh quietly stared at the bodies before the workers spirited them away. It was early yet and there were many more bodies to uncover in the Old City of Mosul.

This was the site of Iraq's landmark military victory just weeks ago that ended the Islamic State in Iraq and Syria's (ISIS) wrenching occupation of Mosul and crippled the militants' odious ambitions for the Middle East, Prime Minister Haider al-Abadi said. There were noisy, flag-waving celebrations, even as the prime minister reminded the nation that there had been "blood and sacrifices" too.

Only now is the terrible cost of the victory emerging, in quarters of the Old City ground to rubble by airstrikes, shelling and suicide bombs. For under the barrage were thousands of homes packed with families. Hundreds of the houses were transformed into graves.

With the rough estimates of the dead from the neighbourhood reaching into the thousands, relatives have angrily questioned the way the battle was fought by Iraqi forces and their partners in the United States-led military coalition, which carried out airstrikes in support.

The concerns over civilian casualties have become more urgent as US-backed forces redouble their efforts to defeat the ISIS in the militants' final redoubts in Iraq and Syria.

Time after time in Mosul, civilians were killed in a similar, disturbing pattern: ISIS militants kidnapped families as human shields in houses that served as the fighters' garrisons. Snipers took up positions on rooftops, firing at Iraqi troops or coalition planes. Then the houses were bombed, sometimes by artillery or airstrikes and with little apparent regard for the people inside, relatives and survivors said.

Basements used for shelter became tombs.

No one has said yet how many died here. Even estimates are a secret, closely held by a government sensitive to the charge that it attacked the neighbourhood with terrifying force and not enough care. But there are grim clues.

At the local morgue, nearly 900 names are on a record of bodies pulled mostly from the Old City since June 24, an official there said. Civil defence workers have a list of 300 locations where bodies are waiting to be recovered and they have reached only a little more than a third of those sites.

In some of the houses, there is one body. In others, there are dozens.

Hundreds of other victims were buried by their relatives during the fighting in gardens or makeshift cemeteries dug in empty lots. The local "refrigerators" at the main morgue in Mosul - two tractor-trailers parked on a lawn - are already full.

"Based on our figures," said one Iraqi official who spoke on the condition of anonymity to discuss a taboo subject, "there are not enough refrigerators in all of Iraq".

Mohammed Ali Mahmoud visited one of the Mosul morgues earlier this month, mingling with others carrying their own tragic tales. His was exceptional: Seventeen members of his extended family were killed in what he said was an airstrike in the Old City.

"They had no mercy. A sniper would fall with a bullet or a rocket. But to kill one sniper, seven houses were destroyed," he said, as another man entered the morgue to request death certificates for 15 members of his family, the victims of a different strike.

If the suffering of Mosul carried a lesson, it was that the government could not afford to disappoint the city's residents ever again and stir the kind of complaints that the militants had exploited. But at the morgue, the dead seemed forsaken among all the talk of victory and as luckier corners of Mosul burst back to life.

Their survivors struggled too - to obtain documents for death benefits, to get medical care for their injuries and to shake the stain of suspicion that they said was attached to residents of the Old City, of sympathy with the ISIS.

The Iraqi military said it made protecting civilians its priority at every stage of the difficult nine-month battle for Mosul, a city that once had nearly two million people, and delayed offensives out of an abundance of caution. "Liberation of people before liberation of the land" was the troops' refrain.

But there were warning signs that Iraqi and US forces might be less restrained as they reached the narrow confines of western Mosul where ISIS fighters were making their last stand - even as it became clear that the militants were increasingly hiding behind civilians.

In late March, the coalition launched an airstrike against the ISIS in the western Mosul al-Jadida neighbourhood that killed at least 100 people. Residents said they had gathered in one of the targeted houses because it was one of the few in the area that had a basement.

The growing concern about civilian deaths is not confined to Mosul. Civilian casualties have been rising across the battlefield against the ISIS in Iraq and Syria because of coalition airstrikes, according to Airwars, a group that tracks the casualties - which it said have approximately doubled since President Donald Trump took office.

US Army Colonel Ryan Dillon, a spokesman for the US-led coalition fighting in Iraq and Syria, said the "coalition's goal is always for zero human casualties. We apply rigorous standards to our targeting process".

He attributed allegations of rising civilian casualties in Iraq to the shift from eastern Mosul to the more densely populated terrain in the west of the city, rather than to any change in strategy.

"Not since World War II has there been an urban assault on a city like Mosul," he said. "The only way to liberate the city was to go house by house and street by street."

And it fell to Iraqi soldiers to rescue civilians, whose only hope was that security forces reached them "quickly enough before they starved to death or were killed by ISIS while trying to flee", he said.

In late July, responding to what it said was "false" speculation about a high number of casualties, the Iraqi military released a partial tally, from western Mosul, saying 1,429 people had been killed. It was unclear whether that included the Old City and the tally has not been updated since.

For surviving relatives, the outrage over the deaths has been followed by the laborious and painful process of recovering the bodies. Relatives call the fatigued, underpaid civil defence workers for help or flag them down in the street. There is no grid search under way and no legion of sniffer dogs.

Instead, when the civil defence workers have time, they travel with the relatives to their houses, trudging together over rubble, boxes of ammunition or the explosive-laden corpses of dead Islamic State fighters.

One day this month, relatives were forced to help with the digging. No one had paid the man who operated the excavator and, as a result, he had not shown up for work in four days, according to Lieutenant-Colonel ​ Rabia Hassan, head of the civil defence team in western Mosul.

It was not the fault of the excavator operator, who, for most of the recovery operation, had been paying for the work from his own pocket, he said. "Nobody cares and nobody asks," he added.

Theirs was backbreaking and perilous work. At one point, smoke rose from an explosion about a block away. Everyone kept digging.

Abosh sat near the rescue vehicles, with the body bags at her feet, sobbing as other relatives watched and waited for their turn.

Mohamed Taha's house was a few blocks away and in it, he said, were the bodies of his two-year-old son, his wife and his mother. He had last seen them months ago, when he left the Old City to check on his livestock. But then the battle lines shifted and he never made it home.

For weeks, Yunis Sallou had been trying to extricate his uncle and three cousins, who were interred in his grandparents' house. As they scraped at the rocks with their hands or with small shovels last week, the smell of the bodies drifted up from somewhere too far down to reach.

Hala Khamis, the survivor of an airstrike more than a month ago, escaped the wreckage with three of her daughters, but not Jassim, her 10-year-old son, who had been in a separate room. She returned to the house with the rescue workers last week, carrying Jassim's first-grade photograph and a can of aerosol deodorant to ward off the smell.

"To be honest, I am not sure he is here. He may have escaped," she said, spritzing the clothes of the rescue workers with the deodorant as if that might speed up their work. A body was found, but it belonged to a militant with a suicide belt still wrapped around his waist. Khamis stumbled around the concrete, imploring the civil defence workers to keep trying.

But there was too much rock and no machine to shift it. They would have to return.

The strike that killed 17 people spared three members of the family. One of them, Ali Hussein Ali, 23, happened to walk out of the room where the family was sitting when the roof collapsed.

He spent 22 hours in the rubble, hearing the voices of his relatives, he said. Half an hour before he was rescued, the voices stopped.