The attacks documented in the report include a March 20 airstrike that targeted a school housing displaced people in the suburban town of Mansourah, outside of Tabqa, as well as another strike that hit a packed marketplace in Tabqa City two days later. Investigators from Human Rights Watch visited the sites of both attacks this July and collected the names of at least 84 civilians who had died in the bombings, including 30 children. While witnesses who spoke to investigators acknowledged that ISIS members, along with their families, had been around the areas of the bombings, they also said many civilians were nearby who had no connection to the group.

U.S. military aircraft bombed a school and a crowded marketplace in attacks that killed dozens of civilians in Syria this March, according to a new report from Human Rights Watch. The report, titled “All Feasible Precautions?: Civilian Casualties in Anti-ISIS Coalition Airstrikes in Syria,” investigated two airstrikes conducted in and around the northern Syrian city of Tabqa. Investigators who visited the sites and interviewed locals and survivors found that the strikes had caused huge numbers of civilian deaths. The documentation adds to a drumbeat of criticism about a U.S. air campaign in Syria that has already been accused of inflicting massive civilian casualties in support of ground operations against Islamic State by the U.S.-backed Syrian Democratic Forces.

All local residents Human Rights Watch interviewed said that it was well known that there were many civilians at both sites. According to local residents, the Mansourah school had long hosted displaced civilians fleeing other parts of Syria, and civilians had used the Tabqa market throughout the years-long war. Any person with local knowledge would likely have been able to identify the substantial risk that the two sites contained significant numbers of civilians.

Human Rights Watch interviewed survivors of the attacks and witnesses, as well as local people who helped bury the victims afterward. Speaking with locals, investigators said it was widely known that both sites frequently had large numbers of civilians present. According to the report:

Ole Solvang, a deputy emergencies director at Human Rights Watch, was one of the investigators who visited the bombing sites after the towns returned to the control of the Syrian Democratic Forces this summer. Solvang said the bombings against civilian targets raise serious questions about U.S. commitment to investigating incidents in which its troops allegedly killed innocent civilians. The military has yet to announce that it will launch a full investigation into either strike and has provided limited information to investigators. “We haven’t received a lot of detail from the military about these cases,” Solvang said, “but we think it is very important that they launch a full investigation into what happened as it appears that large numbers of civilians have been killed.”

In the case of the March 22 marketplace bombing, huge numbers of people who had been lining up to buy bread at a local bakery were killed by an airstrike in an attack that may have been targeting a few ISIS members sitting in a nearby internet cafe. While the U.S.-led coalition has acknowledged carrying out the March 20 attack against the school, which it claimed had targeted a suspected weapons storage facility, it has said that it is still assessing the circumstances surrounding the marketplace bombing.

Human Rights Watch’s estimate for the strikes’ death toll — based on named victims — is likely a conservative number, Solvang said, since many of those killed in the school strike were internally displaced refugees from surrounding areas whose identities were not necessarily known to locals. In response to questions from Human Rights Watch, the U.S. military stated that it had “determined prior to the Mansourah attack” — on the school — “that there was no civilian activity at the site,” but it was still assessing the Tabqa City incident.

A spate of deadly bombings in recent months by the U.S. against marketplaces, schools, and mosques in Syria and Iraq have raised alarms about the type of intelligence the U.S. is using to carry out airstrikes, as well as the criteria being used to determine whether civilians are present at the targeted sites. This March, the U.S. bombed a mosque in the northern Syrian town of al-Jinah, an attack that locals said killed dozens of civilians who had gathered for a religious service. Interviews conducted by The Intercept with survivors indicated that large numbers of innocent people were killed in that attack. The military has said that its investigation into the incident will not be reopened.

“There is a trend here in which the coalition is attacking places that are at least notionally civilians targets, like markets, schools, and mosques, where they presumably have information showing some presence” of militants, said Solvang. “In at least some of these cases, we’ve confirmed that militants were nearby, but even in those cases it doesn’t seem that the coalition knew that there were also many civilians in the area when they carried out their attacks. This makes us seriously question the intelligence they are using, as well as whether they are conducting pattern-of-life analysis to understand the nature of the targets that they are hitting.”

The case of the March 22 marketplace bombing was particularly mystifying to Human Rights Watch investigators. The bombing took place in broad daylight, at 5 p.m., in a crowded marketplace as large numbers of people were queuing to buy bread from a local bakery. The lines of people should have been clearly visible to coalition forces conducting aerial surveillance before the attack was carried out.

As deadly these incidents were, the ones in March represent just two of the thousands of airstrikes that have been carried out by the U.S.-led coalition since the war against ISIS got underway. They are also one of the few major incidents that independent investigators have been able to verify on the ground, having occurred in populated urban areas that are now under the control of the Syrian Democratic Forces. According to the independent monitoring group AirWars, coalition strikes in Iraq and Syria have killed between 5,343 and 8,223 civilians since the bombs began falling in August 2014. This summer, United Nations officials said that there had been “staggering loss of civilian life” during the ongoing offensive to retake the ISIS capital of Raqqa, with civilians being killed by coalition airstrikes, as well as ground battles between the Syrian Democratic Forces and the Islamic State.

In a Time interview earlier this month, Lt. Gen. Stephen Townsend, the top U.S. military officer during much of the coalition effort against ISIS, praised the Trump administration for having “freed us up a bit to prosecute the war in a more aggressive manner.” During his campaign, President Donald Trump had repeatedly promised to wage U.S.-led wars more brutally, including by deliberately targeting noncombatants and re-instituting a policy of torturing terrorism suspects. Many observers of the campaign against ISIS have criticized the military’s conduct, suggesting that the impact of widespread civilian casualties was transforming the coalition in the eyes of locals from liberator into aggressor.

Responding again to the growing outrage over the campaign in an article published in Foreign Policy last week, Townsend insisted that the war was being waged proportionately, adding that responsibility for any civilian deaths lay solely with ISIS. “The coalition will continue to take great care in our targeting to protect civilians from harm but we must maintain our course,” Townsend wrote. “We must maintain the initiative and we must liberate the people of Iraq and Syria from this real and mortal danger.”