The two groups published their findings Thursday on a website titled "Rhetoric versus Reality." They say the report is the result of 18 months of research of open-source materials, social media postings and satellite imagery, followed by two months of ground investigations in Raqqa.
Retaken from ISIS in October 2017 by U.S.-backed Syrian forces, the city in central Syria had become the defacto capital of the terror group's self-declared Caliphate. Between June and October 2017 coalition aircraft carried out an intense bombing campaign against ISIS targets in the city to help the Kurdish fighters capture the city.
"Many of the air bombardments were inaccurate and tens of thousands of artillery strikes were indiscriminate, so it is no surprise they killed and injured many hundreds of civilians," said Donatella Rovera, senior crisis response adviser at Amnesty International.
"First and foremost, any unintentional loss of life during the defeat of Daesh is tragic," said Colonel Scott Rawlinson, a spokesman for the Operation Inherent Resolve, the U.S.-led coalition fighting ISIS, which also known as Daesh.
"However it must be balanced against the risk of enabling Daesh to continue terrorist activities, causing pain and suffering to anyone they choose," Rawlinson added.
Overall, the coalition has determined that 318 civilians were killed in Raqqa between October 2014 and October 2017, after investigating 69 credible allegations. Additional allegations are still being investigated.
"The coalition and the U.S. have provided extensive information to Amnesty International on our targeting process including multiple background briefings on targeting with regard to the mitigation of civilian casualties and extensive written responses to requests for information," said Lt. Colonel Earl Brown, a spokesman for U.S. Central Command.
"Additionally, the Deputy Undersecretary of Defense for Policy briefed Amnesty International, Airwars, and other NGOs on our constant efforts to improve" he added.
Rawlinson said Amnesty International "provided us with 86 new allegations, 43 of which had already been assessed as credible and previously reported or were deemed not credible because the allegation did not corroborate with our strike records."
"We requested that Amnesty International provide us with additional information on the remaining 43 allegations if they have it so that we would be able to determine whether we could conduct an investigation," said Rawlinson. "The Coalition takes all reasonable measures to minimize civilian casualties."
The coalition has extensive procedures in place to ensure that its airstrikes do not result in civilian casualties and also investigates any credible allegations of civilian casualties.
So far those investigations have determined that at least 1,291 civilians have been unintentionally killed in the 34,464 airstrikes against ISIS targets that have been carried out from August 2014 to March 2019.