Syria conflict: UN suspends all aid after convoy hit.

The UN has suspended all aid convoys in Syria after a devastating attack on its lorries near Aleppo on Monday.

The strikes, which witnesses say came from the air, came hours after Syria declared a week-old US-Russia brokered cessation of hostilities at an end. Russia and Syria have both insisted that their forces were not involved.

But UN chief Ban Ki-moon launched a stinging attack on the Syrian government, saying it had killed the most civilians in the civil war.In unusually blunt language, Mr Ban said "powerful patrons... feeding the war machine, also have blood on their hands". Diplomats are now scrambling to salvage the ceasefire deal, with US and Russian officials holding talks in New York on Tuesday.

The attack at Urum al-Kubra destroyed 18 of 31 lorries and killed about 20 civilians, including a senior local official of the Syrian Arab Red Crescent, aid officials said.

Russian defence ministry spokesman Igor Konashenkov said that after studying video taken at the scene they "did not find any signs of munitions hitting the convoy".

"Everything shown in the video is the direct result of a fire which mysteriously began at the same time as a large scale rebel attack on Aleppo," he said.

The Syrian military, quoted by state media, said there was "no truth" to reports that the army had targeted the convoy.

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A media activist who witnessed the attack told the BBC Arabic service that Russian reconnaissance planes had been spotted, apparently filming the passage of the convoy.

He said the first strike came at about 19:00 local time on Monday, when a helicopter dropped several barrel bombs. This was followed by rocket and machine-gun fire from aircraft, he said.. Just a day ago, aid workers in Geneva were "almost celebrating" one said, because all the necessary permits had been received, all the warring parties had been notified, and a convoy was finally going to Aleppo province.

The 31 lorries were carrying supplies for 78,000 people in Urum al-Kubra. But this morning, the optimistic mood had changed.

Aid workers familiar with some of the world's most brutal conflicts were in shock, some close to tears, others expressed disgust. Vitamins and blankets, books and pencils for children, medicines to treat burns or diabetes have all been destroyed.

The head of the Syrian Arab Red Crescent's office in Urum was killed, dying of his injuries as he waited hours to be evacuated. Now the UN and the Red Cross have suspended aid deliveries. Millions of Syrians who had hoped the brief ceasefire might bring some relief will, a Red Cross spokesman said, go on suffering, "and they have been for years".

Ban Ki-moon, in his final address as UN Secretary-General to the UN General Assembly in New York, said many groups had killed innocents in Syria "but none more so than the government of Syria, which continues to barrel-bomb neighbourhoods and systematically torture thousands of detainees".

He called the attack on the aid convoy "sickening, savage and apparently deliberate" and called for those responsible to be held to account.

A UN spokesman said earlier that the convoy had received proper permits, and all warring parties - including Russia and the US - had been notified.

The President of the International Committee of the Red Cross, Peter Maurer, denounced the attack as a "flagrant violation of international humanitarian law".

Syrian Red Crescent President Abdulrahman Attar said: "It is totally unacceptable that our staff and volunteers continue to pay such a high price because of the ongoing fighting."

The US expressed "outrage" over the attack. Washington has said it will "reassess the future prospects for co-operation" with Russia - an ally of Syria's government.

Aid deliveries to besieged areas had been a key part of the cessation of hostilities deal brokered last week.The convoy was being unloaded at a Red Crescent warehouse when the attack began. The aid had been due to be delivered to people in rebel-held areas around Urum al-Kubra, who were last supplied in mid-July.A health clinic near the warehouse was also badly damaged.The attack appeared to signal the collapse of the latest effort by the US, which backs the rebels, and Russia to halt the violence in Syria.The Syrian military and rebels have accused each other of widespread violations.

The Mariana DAngelo Editorial Group