The US has concluded that Russian warplanes bombed a humanitarian aid convoy and warehouse in Syria Monday (19 September) night. The convoy and warehouse, which belong to the Syrian Arab Red Crescent, were located in the area of Urum al-Kubra.

"All the evidence we have points to that conclusion," a US official told CNN. The overnight bombing west of Aleppo led the UN to halt its own aid operations in the war ravaged nation. The bombing killed around 20 civilians as well as the director of the Red Crescent's Urum al-Kubra branch, Omar Barakat.

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US Colonel John Thomas earlier made clear that the attack was not part of coalition military action, thus leading to the conclusion the bombing had been led by either Russia or Syria. "It was certainly not the coalition who struck from the air; it does look like an airstrike," he said, adding, "the only other entities that fly in Syria are Russia and Syria."

Officials said that the Russian and Syrian governments were made aware in advance to the 31-truck convoy to make sure it would not be bombed by their forces, The Wall Street Journal reported. "There was coordination ahead of time with the Russians," an unnamed US official said.

The conclusion by the US government contradicts statements by Moscow and Damascus, which denied involvement in the bombing of the aid convoy. Moscow also released drone footage of what it claimed was the convoy being used as cover for an armed truck, said Sky News reported.

"The examination of the video footage made via drones of the movement of the humanitarian convoy in areas controlled by militants in the province of Aleppo has revealed new details," Russian Major General Igor Konashenkov said. "The video clearly shows how terrorists are redeploying a pickup with a large-calibre mortar on it using the convoy as a cover."

According to the Wall Street Journal, the Russian military claimed it observed "no signs" of the convoy being hit by an airstrike. Russia's military also attempted to undermine the account of activists who provided video evidence of the attack.

UN Secretary General Ban Ki-moon called the attack "sickening, savage and apparently deliberate," CNN reported. "Just when we think it cannot get any worse, the power of depravity sinks lower," Ban said during the UN General Assembly annual meeting.

In his own statement, US President Barack Obama said: "Those in Syria and elsewhere who risk their lives to deliver aid to people in dire need...the entire world is in their debt."