U.S. Officials Say Russia Probably Attacked U.N. Humanitarian Convoy

U.S. Officials Say Russia Probably Attacked U.N. Humanitarian Convoy

By ERIC SCHMITT, MICHAEL R. GORDON and SOMINI SENGUPTASEPT. 20, 2016 New York Times

The bombed trucks: “Just when we think it cannot get any worse, the bar of depravity sinks lower.” Banki Moon 

Credit Ammar Abdullah/Reuters

Russia was probably responsible for the deadly bombing of a United Nations humanitarian aid convoy in Syria, American officials said Tuesday, further shredding what remained of a severely weakened agreement between the United States and Russia aimed at halting the war.

Aghast at the attack on Monday night, United Nations officials on Tuesday suspended all aid convoys in Syria, describing the bombing as a possible war crime and a cowardly act.

The suspension was announced as the United Nations was convening its annual General Assembly meetings in New York, where the five-year-old Syria war has become the organization’s most anguishing challenge.

“Just when we think it cannot get any worse, the bar of depravity sinks lower,” Secretary General Ban Ki-moon said in his opening remarks to the gathering, his last as leader of the United Nations after 10 years. Mr. Ban called the attack on the convoy “sickening, savage and apparently deliberate.”

Publicly, the Obama administration said it held Russia responsible, in its role as a sponsor of the partial cease-fire agreement that it reached last week with United States. But the Americans still held out the possibility of salvaging the agreement. Benjamin Rhodes, the deputy national security adviser, said Russia should have ensured a halt to air operations in an area where “humanitarian assistance is flowing.”

Privately, American officials said their intelligence information suggested Russian aircraft had actually carried out the attack.

The American officials said that the Obama administration wanted to allow Moscow the time and space to investigate and announce its own conclusions about the bombing, which destroyed 18 of 31 trucks authorized to travel to a rebel-held area in northern Syria.

The bombing was the second disaster in three days to subvert the agreement between Russia and the United States, which had called for a weeklong cease-fire, humanitarian aid deliveries, collaboration by the two powers on targeting militant extremists in Syria and a buildup of trust to eventually resume peace talks.

On Saturday, an errant American airstrike that was supposed to target Islamic State militants in Syria instead killed 60 people that Syria’s government and its Russian allies identified as Syrian soldiers; they suggested that the assault was deliberate, despite American apologies.

The United States has the ability to track warplanes and other aircraft in the region — through radar and other sensors — and the Pentagon has determined with “very high probability” that a Russian Su-24 attack plane was directly over the convoy less than a minute before the airstrike was reported, a senior American official said.

“We have a very good picture of the skies over Syria, as well as where there’s activity,” the official said. “We know the plane in question was Russian, not Syrian, and was directly overhead.”

American analysts are assessing photographs of the bomb damage that could be tied to the weapons the Su-24 carries. They are also checking for any intercepted communications from the Russian pilot to determine why the convoy was struck.

“We have no indication that anything other than Russian tactical aircraft were in the air at the time the convoy was struck, to include both strike and reconnaissance aircraft,” said another American official. “We have seen no indication that it was anything other than an airstrike.”

The officials spoke on condition of anonymity because they were discussing classified intelligence information.

Col. John J. Thomas, a spokesman for United States Central Command, told reporters at the Pentagon on Tuesday that warplanes of the American-led coalition that is fighting the Islamic State in Iraq and Syria had not carried out the attack. “We’ll look to the Syrians and the Russians to tell us what they know,” he said.

The strike on the trucks, which were carrying critically needed food and medical supplies bound for rebel-held areas of Syria’s western Aleppo Province, took place shortly after the Syrian military declared that it regarded the seven-day partial cease-fire as over.

The convoy, escorted by the Syrian Arab Red Crescent, was among the first to try to deliver humanitarian aid to rebel-held areas under the cease-fire agreement. Members of the group said its local chief, Omar Barakat, was among at least 12 people killed in the attack, though United Nations officials in Geneva said the death toll was uncertain.

The International Committee of the Red Cross said in a statement that about 20 civilians were killed and much of the aid destroyed. Peter Maurer, the organization’s president, called the attack a “flagrant violation” of international law.

While both Syria and Russia denied responsibility for the bombing, the Russian account evolved over 24 hours.

The ruins of the convoy on Tuesday. “We know the plane in question was Russian, not Syrian, and was directly overhead,” a United States official said. Credit Omar Haj Kadour/Agence France-Presse — Getty Images

Some Russian officials suggested that artillery fire from rebels had hit the convoy. Later, some officials suggested the trucks had been set on fire. On Tuesday afternoon, Russia’s Defense Ministry said a drone video had shown that a “terrorists’ pickup truck” armed with a mortar had accompanied the convoy, the Tass news agency reported. This appeared to raise the possibility that the intended target had been a vehicle of militants.

But the drone video shows the aid convoy stationary, at the side of the road, and what appears to be a truck towing a mortar passing by. The video does not appear to establish any further connection between the convoy and the mortar truck, nor anything that would make the convoy a legitimate target.

The head of the United Nations agency that coordinates aid, Stephen O’Brien, said the attack would amount to a war crime if it were found to have targeted humanitarian aid workers.

He called for an independent investigation.

“In terms of aid worker victims, this particular incident of an aerial bombing of an aid convoy is unprecedented in scale,” said Abby Stoddard, who studies attacks on aid workers for Humanitarian Outcomes, a research and advocacy group.

Witnesses said multiple strikes had hit the convoy as workers were unloading aid, and then hit rescue workers who arrived to help the injured.

United Nations officials said 18 trucks — clearly marked and carrying wheat flour, nine tons of medicine and clothing for about 78,000 people — were destroyed. Benoit Carpentier, a spokesman for the International Federation of Red Cross and Red Crescent Societies, said a hospital had also been destroyed.

Aid convoys have endured sniper fire and shelling during the five years of the Syrian conflict, but the attack on Monday is thought to be the first time one was hit by an airstrike.

John Kirby, a spokesman for the State Department, called the attack on the convoy an “egregious violation” of the agreement with Russia.

Mr. Kerry conferred with his Russian counterpart, Foreign Minister Sergey V. Lavrov, and other diplomats representing the International Syria Support Group in New York on Tuesday morning as the United Nations General Assembly session got underway.

The support group, a 17-nation effort to halt the conflict that is led by Mr. Kerry and Mr. Lavrov, planned to hold additional meetings this week.

Eric Schmitt reported from Washington, Michael R. Gordon from New York, and Somini Sengupta from the United Nations. Reporting was contributed by Nick Cumming-Bruce from Geneva; Helene Cooper from Washington; Anne Barnard from Beirut, Lebanon; Sophia Kishkovsky from Moscow; and Rick Gladstone from New York.

A version of this article appears in print on September 21, 2016, on page A1 of the New York edition with the headline: U.S. Ties Russia to Strike on U.N. Convoy in Syria. Order