“Throughout the entire length of the battle for Aleppo, there have been multiple claims of violations of human rights and multiple denials,” said Eliot Higgins, a senior fellow at the Digital Forensic Research Lab of the Atlantic Council.
“What we have been able to present now is a wealth of evidence confirming the targeting of civilian structures, namely hospitals, which in certain cases has been denied by the Russian Ministry of Defense,” he added. “We have been able to confirm the use in civilian areas of a variety of indiscriminate weapons.”
Syrian forces, backed by Hezbollah fighters, Iran’s paramilitary Quds Force and Russian air power, took Aleppo in late December. The capture of the city was an important milestone that gave the government of President Bashar al-Assad control over all of Syria’s major cities and strengthened Moscow’s hand in discussions over the country’s future.
But while the Atlantic Council report acknowledges that his victory in Aleppo has solidified Mr. Assad’s hold on power, at least for now, it argues that the ruthless strategy and tactics used by the Syrian and Russian governments would make the Syrian president “a poor if not harmful partner” in efforts to defeat the Islamic State and other extremist groups.
Experts at the Atlantic Council have long urged the United States to do more to protect civilians in Syria and support the moderate opposition. In the report, the group employs hard evidence, including satellite images from DigitalGlobe, a commercial satellite company, fresh accounts from Syrian activists on the ground and photography published by Russia’s Defense Ministry.
A reconstruction of one key episode — the July 16 bombing of another hospital, known as M2, in the Maadi district — was carried out by Forensic Architecture, a research organization at Goldsmiths, University of London, which was asked to take an independent look at the video and photographic evidence of the bombing.
Aleppo was divided in July 2012 between government- and opposition-controlled areas. With the support of Russia, the Assad government began a major offensive in September of last year to take the city.
Fragile and temporary cease-fires were used by the Syrians and their allies to prepare fresh offensives, which, despite Russian and Syrian denials, often targeted civilian areas.
One claim that the Atlantic Council report challenges was issued by Lt. Gen. Sergei F. Rudskoi, the head of the operations directorate of the Russian general staff, who insisted in October that no damage had been done to the al-Sakhour hospital in a Russian bombing raid. To buttress his case, General Rudskoi displayed satellite photos that he said had been taken between Sept. 24 and Oct. 11. Eyewitness accounts to the contrary, he added, were “mere fakes.”
But a comparison of DigitalGlobe satellite photos taken on Sept. 25 and Oct. 13, the Atlantic Council report notes, shows the emergence of a large bomb crater near the hospital, also known as M10, and damage to the hospital building. Security camera videos from inside the hospital offer corroborating evidence of an Oct. 3 attack, as does a photo from the street by a local resident.
The report concludes that there were several reasons to think the attacks on the medical centers were deliberate, including the large number of strikes, the Assad government’s knowledge of the terrain, and the Syrian government’s practice of confiscating medical supplies from humanitarian aid convoys.
The M2 hospital was damaged by air and artillery strikes at least a dozen times between June and December.
Other photographic evidence points to the use of incendiary munitions and cluster bombs. The Kremlin-backed television channel, Russia Today, provided some of the evidence in video footage it showed in June that had been taken at a Russian air base near Latakia, Syria. (The version of the report that was later uploaded to YouTube deleted the images of the weapons being mounted on a Russian warplane.)
When a Russian team later entered eastern Aleppo to clear away unexploded ordnance, a photograph published by the Russian Defense Ministry showed the remains of cluster bombs, the Atlantic Council report notes.
A variety of reports from victims and video on YouTube indicate that Syrian government attacks with chlorine gas increased in the final phase of the battle for Aleppo. One video “showed a chlorine gas cylinder with its labels intact,” the report said.
The use of chlorine bombs by the Syrian government, Mr. Higgins said, continued even after reports confirming their use were made by the United Nations and an international watchdog organization in The Hague that enforces the ban on the use of chemical agents in war.