Analysis of satellite imagery of a deadly attack on an aid convoy in Syria last month showed that it was an air strike, a UN expert has said, in remarks that were later toned down to say it was not a conclusive finding.
Some 20 people were killed in the attack on the UN and Syrian Arab Red Crescent convoy at Urem Al-Kubra, near the northern city of Aleppo.
The attack also destroyed 18 of 31 trucks, a warehouse and clinic.
The United States blamed two Russian warplanes which it said were in the skies above the area at the time of the incident. Moscow denies this and says the convoy caught fire.
“We had an image of that and could clearly see the damage there. With our analysis we determined it was an air strike and I think multiple other sources have said that as well,” Lars Bromley, research adviser at the UN Operational Satellite Applications Programme (UNOSAT), told a news briefing.
“For air strikes, what you are usually looking out for is the size of the crater that is visible and the type of crater,” he said. A giant crater was caused “almost certainly (by) airdropped munitions” as opposed to artillery or mortars, he said.
UNOSAT manager Einar Bjorgo, who took part in the briefing, contacted Reuters hours later to say it was not possible to be 100%. “There is significant damage, and we believe it maybe air strikes, but it’s not conclusive.
“Our observations of the imagery show indications of it possibly being an air strike. But it’s a very damaged area and we cannot definitely conclude that it’s an air strike,” he said.
The United Nations has referred officially only to an “attack”, which led to a brief suspension of its convoys in Syria. The International Federation of Red Cross and Red Crescent Societies initially referred to “air strikes” in a statement.
UN Secretary-General Ban Ki-moon said last Friday he would establish an internal UN board of inquiry to investigate the attack and urged all parties to fully cooperate.
UNOSAT, which reviews only commercially available satellite images, has not been asked to share its analysis with the UN investigators, but is prepared to do so, Mr Bjorgo said.
“Our images are from time to time used in order to brief Security Council members,” he said.
Mr Bjorgo, speaking generally, said: “We are neutral. We don’t have a political agenda, we simply state the facts.”
UNOSAT has mapped Syria’s conflict since it began in 2011, using satellite imagery to assess population movements and damage to civilian infrastructure.
This enables UN agencies trying to deliver food and medical assistance to besieged areas to view roadblocks and checkpoints in real time.