MOSUL, Iraq – A sharp rise in the number of civilians reported killed in U.S.-led airstrikes in Iraq and Syria is spreading panic, deepening mistrust and triggering accusations that the United States and its partners may be acting with an unprecedented disregard for lives of noncombatants.

The escalation comes as local ground forces backed by air support from a U.S.-led coalition close in on the Islamic State’s two main urban bastions – Raqqa in Syria and Mosul in Iraq.

In front-line neighborhoods in western Mosul, families described cowering in basements for weeks as bombs rained down around them and the Islamic State battled from their rooftops. Across the border in Raqqa, residents desperately trying to flee before an offensive begins are being blocked by the militants, who frequently use civilians as human shields.

Throughout his election campaign, President Donald Trump pledged to target Islamic State militants more aggressively, criticizing the U.S. air campaign for being too “gentle” and asking for a reassessment of battlefield rules. The United States has denied there has been any shift and defended the conduct of its campaign.

But figures compiled by monitoring organizations and interviews with residents paint an increasingly bloody picture, with the number of casualties in March already surpassing records for a single month.

The worst alleged attack was in Mosul, where rescue teams are still digging out bodies after what residents describe as a hellish onslaught in the Mosul al-Jadida neighborhood during the battle to retake it two weeks ago. Iraqi officials and residents say as many as 200 died in U.S. -led strikes, with more than 100 bodies recovered from a single building. The U.S.-led coalition says it is investigating the reports but has acknowledged carrying out a strike against militants in the area.

The wooden carts that residents use to carry vegetables and other wares in the once busy market area instead ferried out cadavers recovered from the rubble last week.

Amnesty International on Tuesday said the coalition was not taking sufficient precautions to prevent civilian deaths in Mosul, in a “flagrant violation” of international humanitarian law.

It was just one of numerous incidents across Iraq and Syria in recent weeks that have raised concerns that the United States has flouted rules requiring it to protect civilians. In both countries, local politicians and activists say the high numbers of deaths are spreading alarm among civilians and sewing distrust of the U.S.-backed campaign advancing toward their homes.

“People used to feel safe when the American planes were in the sky, because they knew they didn’t hit civilians,” said Hussam Essa, a founder of Raqqa is Being Slaughtered Silently, which monitors violence in Raqqa province. “They were only afraid of the Russian and regime planes. But now they are very afraid of the American airstrikes. It is only American planes that are active, and they are targeting everywhere.”

According to the U.K.-based organization Airwars, which tracks allegations of civilian deaths in airstrikes, out of 1,257 claims of deaths in U.S.-led coalition airstrikes this month, a record 337 have been assessed as being “fair,” meaning that there is a reasonable level of public reporting of the alleged incident from two or more generally credible sources and that strikes have been confirmed in the vicinity on the day in question.

“The scale of the destruction is huge, and we are reeling from the number of alleged cases, not just in Mosul but in Raqqa, too,” said Chris Woods, the director of Airwars. “Casualty numbers from western Mosul are absolutely shocking. In Syria it’s a car here, a family there. It happens every day.”

The group has stopped monitoring Russian strikes in Syria, in order to focus on accusations linked to the U.S.-led coalition, saying its organization is overwhelmed. In the first two months of the year, U.S. strikes were responsible for more civilian casualties than Russian strikes for the first time since Russia intervened in 2015, according to Airwars figures. Russian strikes are now climbing again as a partial cease-fire collapses.

“In Raqqa they haven’t yet completed the encircling, and yet there’s been a huge jump in reported casualties from coalition strikes since Trump,” Woods said. “That is an indication that the U.S. is taking less care.”

Woods said the intensification began during the Obama administration but escalated under Trump. In December, the U.S.-led coalition delegated approval to battlefield commanders in Mosul, speeding up the responsiveness of strikes after a tough battle for the eastern part of the city. The coalition says strikes are subject to the same scrutiny.

“There is no military force in the world that has proven more sensitive to civilian casualties,” Defense Secretary Jim Mattis said Friday. “We are keenly aware that every battlefield where an enemy hides behind women and children is also a humanitarian field, and we go out of our way to always do everything humanly possible to reduce the loss of life or injury among innocent people.”

The escalation of U.S. strikes around the city of Raqqa ramped up in February as the United States intensified efforts to train and equip a Syrian force in preparation for an offensive against the city, expected to begin in the coming months.

In March, the tempo increased further, with more sites being targeted that have no obvious military value, according to a Syrian living in Turkey who is from Raqqa and is in regular contact with his family and friends who are still there. “They are hitting everything that isn’t a small house,” he said, including the barges that ferry passengers across the river dividing the city now that the bridges have been disabled.

Among the bigger incidents was a strike last week on a farmhouse sheltering displaced people in the town of Mansoura outside Raqqa that killed at least 30 people, according to monitoring groups. An attack on a mosque in western Aleppo that the U.S. military said was aimed at known al-Qaida operatives also appears to have killed dozens of people attending prayers, according to witness accounts and monitoring groups.

A wave of continued attacks in the past week in the small town of Tabqa has added to a record toll of 101 civilians killed by U.S. strikes from the beginning of the month to March 21, Essa said. He provided the names of 41 people alleged to have been killed in a three-day period last week in strikes that hit a bakery, a carwash, a slaughterhouse and other targets.

In Iraq and Syria, there has also been a discernible shift in the kinds of targets being hit – with infrastructure such as hospitals and schools coming under fire. The U.S.-led coalition contends that militants are increasingly using such protected buildings as bases for attack, knowing that there are restrictions on bombing them under U.S. rules of engagement.

Tabqa is a crucial step on the path to Raqqa, and it is the current focus of the battle. Reports that the Tabqa dam have also been hit by airstrikes during the fighting have further contributed to the sense of panic after the Islamic State issued a warning on Sunday that the dam could burst.

Downstream from the dam, residents are terrified by the intensified bombing and of the risk of a dam breach, the Syrian said. His family is desperate to escape, but the Islamic State has erected checkpoints to prevent people from fleeing. “People don’t know what to do,” he said.

In Iraq, too, civilians are trapped as Iraqi forces push into the most densely packed areas of Mosul, including the Old City, where an estimated 400,000 people are trapped in old structures on narrow streets.

The United Nations said that at least 307 civilians have been killed and 273 wounded in western Mosul since Feb. 17, warning Iraqi security forces and the coalition to avoid falling into the Islamic State’s “trap” as the group deliberately puts civilians in danger.

With a large amount of artillery and ordnance being fired into the city, though, it is also hard to ascertain which deaths the coalition is responsible for, Woods said. Iraqi commanders, who call in airstrikes from the U.S.-led coalition, say its difficult for them to know whether civilians are in houses when many are stuck inside for weeks at a time and it is not possible to see them through drone surveillance.

Lt. Gen. Abdul Ghani al-Asadi, commander of Iraq’s counterterrorism units, said the troops are instead relying on tips from those fleeing as to which houses have civilians inside.

Still, Mosul Eye, a monitoring group in the city, said it had warned Iraqi forces that civilians were trapped in homes in Mosul al-Jadida days before the U.S. strike there and sent coordinates.

Amnesty International said that because the government has told residents to stay in their homes, the U.S.-led coalition should have known that strikes would be likely to result in significant numbers of civilian casualties.

For civilians, many of whom are trapped and unable to leave, the situation is dire.

Nour Mohammed’s family of 23 people hid in a basement in western Mosul for nearly two weeks as explosions rang out around them, crammed into an area of just 12 square meters.

Islamic State militants forced the family to keep the front door open so that they could move in and out of the building freely and fend off the advancing Iraqi forces from the roof.

“We were terrified every time we’d hear the sound of an airplane that they’d bomb us all,” she said as she fled the city last week.

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Sly reported from Beirut. The Washington Post’s Mustafa Salim in Mosul contributed to this report.

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