In a military-run clinic near the front lines in eastern Mosul that receives dozens of civilians and soldiers every day, a woman who was gravely ill held a baby after receiving a botched injection in territory controlled by the Islamic State. (Emilien Urbano/MYOP for The Washington Post)

They came to the clinic in Humvees or beat-up cars, twisted in pain or far beyond saving. An Iraqi special forces soldier, his body gutted by an explosion. Four children with lacerated faces, survivors of a car bomb that had set their house on fire. Another soldier, who had stumbled into a booby trap, pale on his stretcher with a hole in his chest.

The luckier ones trudged past the facility in eastern Mosul, looking for shelter. “The mortars are falling,” said an elderly man, one of hundreds of people displaced by the grisly battles on this side of the city. There was no water or electricity in his neighborhood, he said, and no way to stay home.

“The mortars,” he repeated.

In a field clinic in eastern Mosul, two brothers injured by a car bomb are treated by Iraqi army medics. Islamic State militants have sent hundreds of car bombs to delay approaching troops, deployed snipers on rooftops and launched mortar shells with abandon into residential neighborhoods. (Emilien Urbano/MYOP for The Washington Post)

Civilian and military casualties are mounting as misery spreads in Mosul six weeks after the Iraqi army launched an offensive to capture the city from the Islamic State. Nearly 600 civilians have been killed, according to one estimate, along with dozens of Iraq’s elite, U.S.-trained special forces soldiers — the vanguard fighters in the deadliest battle yet during Iraq’s two-year struggle to vanquish the extremists.

The carnage has slowed the army’s advance and revived debate about the wisdom of the battle plan, which envisioned Mosul’s residents sheltering in their homes — a means, it was hoped, of staving off a mass dislocation and the city’s destruction. Iraqi commanders say they are refraining from using heavier weapons to save residents’ lives, but at the cost of headway on the ground. They also say their U.S. allies are urging them to consider steps that could ease the civilian toll but also hasten a shared victory against the Islamic State in the waning days of the Obama administration — or at least show signs of progress. 

Maj. Gen. Sami al-Aridhi, commander of the Iraqi special forces’ 3rd
Division, is one of the military leaders grappling with the government’s decision, as the battle got underway, to instruct Mosul’s inhabitants to stay in their homes. 

“If there were no civilians, we would have reached the river,” he said, speaking of the Tigris, which bisects the city and now serves as a taunting reminder to the soldiers of the difficult miles to go before even half the city is theirs.

But with the Islamic State intentionally targeting civilians, any plan to evacuate them was fraught with risk, Aridhi added. “If they suffer, it will be on us.”

The battle for Mosul was never going to be easy. Concerns about the complexity of staging such an operation in a city of more than a million people delayed the offensive for more than a year. And Mosul’s symbolic value to the Islamic State, as the most populous city it has controlled, ensured its forces would not leave without a fight. 

Even so, the extremists’ resistance has been more vicious than many feared. They have sent hundreds of car bombs to delay the approaching troops, deployed snipers on rooftops and rained down mortar shells on residential neighborhoods. 

On the day Salem al-Mawla left his neighborhood in eastern Mosul two weeks ago, the Islamic State attacked the army with three car bombs and three suicide bombers, he said. He returned to his home Friday, to pick up medicine and other valuables. “There are people dead in the rubble of their houses,” he said. The homes that remained intact were being ransacked by looters.

Nearly 600 civilians have died in the fighting, according to one estimate. “Many people died inside the city,” a local official said. “Their families couldn’t evacuate them, and buried them in their gardens.” (Emilien Urbano/MYOP for The Washington Post)

Another man, walking with a limp after fleeing the Aden neighborhood, said the army had ordered his family to leave after the Islamic State started directing mortar fire into the area Friday. “Lots of people died. Too many people,” he said, before gunfire erupted from a nearby apartment complex and he was forced to find cover.

Khalaf al-Hadidi, a member of the provincial council, estimated that more than 550 civilians had been killed by Islamic State militants during clashes or in coalition airstrikes. An Iraqi government health official said he could not confirm the death toll.

 “Many of those who died, died on their way from Mosul to Irbil, because it takes long time in each checkpoint,” Hadidi said, speaking about the journey from front-line clinics to the capital of the Kurdish autonomous region. “And many people died inside the city. Their families couldn’t evacuate them, and buried them in their gardens.”

The escalating toll and hardships in eastern Mosul appear to underscore the limits of the current strategy, which has exposed military forces to close-range firefights — with the casualties crippling some elite units — even as it leaves civilians in recently captured areas vulnerable to the Islamic State’s relentless shelling. Officials are also concerned about the slow advance of anti-Islamic State forces north of the city.

Maj. Gen. Najim al-Jabouri, the head of Nineveh Operations Command, said that Iraqi commanders have been divided about whether encouraging a large-scale exit of residents would allow troops to sweep across the city more quickly or bog them down.

“Some commanders, their view is that it’s better if we keep the people outside the city,” Jabouri said. Not only would the civilians be safer, their argument goes, but then Iraqi troops could deploy heavier weapons and intensify air and artillery attacks on military sites, undermining the jihadists’ ability to launch punishing counterattacks.

Other commanders oppose that idea, pointing out that an evacuation would subject civilians to sniper fire and other attacks as they left and that a massive flow of refugees would increase the odds of militant infiltration.

The prospect of an exodus has alarmed officials in Baghdad, who fear it would overwhelm humanitarian organizations already scrambling to keep refugees warm and fed in camps outside the city. Officials with the aid organizations have also reacted with caution. 

So far during the Mosul offensive, “the army has made civilian protection central,” said Lise Grande, the United Nations’ humanitarian coordinator for Iraq. Any large-scale, uncoordinated attempt to evacuate the city’s civilians, she said, could put “hundreds of thousands of people at grave risk going into a bitterly cold winter.” 

Residents flee fighting in eastern Mosul this month. The rising death toll has slowed the army’s advance and led to renewed debate about the wisdom of the battle plan, which envisioned Mosul’s residents sheltering in their homes to avoid a massive outflow of refugees. (Emilien Urbano/MYOP for The Washington Post)

Iraqi Prime Minister Haider al-Abadi, together with the country’s top military leadership, has decided against a mass evacuation for now, a senior Iraqi official said, embracing instead a plan to ask residents of recently cleared neighborhoods to move temporarily to more secure areas nearby, until the threat of militant holdouts and shelling can be allayed.

The commanders’ reasoning: “There is no place for more than a million people,” the official said, speaking on the condition of anonymity to describe internal discussions.

U.S. officials in Baghdad declined to comment on military advice to the Iraqi government. “This is a constant effort,” said Col. John Dorrian, a U.S. military spokesman in Baghdad. “It’s not something where you chisel a plan in concrete; you’re constantly evaluating your progress.”

A U.S. official who spoke on the condition of anonymity said the Obama administration has been working closely with Abadi’s government to ensure that troop movements and preparations for refugee flows were properly calibrated in response to Islamic State actions. 

One step that U.S. officials are urging Iraqi leaders to take is the mobilization of a hold force that could ensure that militants don’t infiltrate recently recaptured areas and prolong the battle with attacks from the rear. 

Iraqi and coalition forces have already adjusted some tactics in response to the Islamic State defense measures.

In recent weeks, American officials say, U.S. planes have expanded strikes designed to “crater” roads in Mosul, in an effort to impede the movement of massive car bombs that the Islamic State has used to ambush local units or bases. Iraqi and U.S. officials are also racing to respond to the retaliatory shelling on cleared neighborhoods. Iraqi commanders are now relaying coordinates of mortar positions to the U.S.-led coalition so its aircraft can attempt to destroy them.

“They may fire two or three, but there won’t be a fourth,” said Lt. Gen. Abdul Ghani al-Asadi, the head of Iraqi special forces.

The measures failed to stop the car bomb that struck Mohamed Yehya’s family and landed him in the clinic, watching as doctors treated his injured wife and four children. The army had entered his neighborhood Thursday, and on Friday, the Islamic State hit back, with an attack that set Yehya’s house on fire. 

“We thought we were secure,” he said. “We thought the army was in control.”

Fahim and Salim reported from Mosul; Ryan reported from Irbil, Iraq.