CAIRO _ The United Nations suspended humanitarian aid deliveries to Syria after an attack killed 21 civilians unloading supplies northwest of embattled Aleppo at the end of the weeklong cease-fire, officials said Tuesday.
The attack Monday night struck 18 of 31 trucks in an aid convoy in rural Urem al-Kubra, damaging the group's warehouse and health clinic. Those killed included at least one leader of the Syrian Arab Red Crescent aid agency.
"We're totally devastated by the deaths of so many people, including one of our colleagues," Abdulrahman Attar, president of the agency, said in a statement.
Staff and volunteers "continue to pay such a high price because of the ongoing fighting," Attar said.
U.N. Secretary-General Ban Ki-moon assailed the "cowards" who carried out the "sickening, savage and apparently deliberate attack" on the aid convoy in Syria.
"Just when we think it cannot get any worse, the bar of depravity sinks lower," he told world leaders at the U.N. General Assembly in New York. "The humanitarians delivering life-saving aid were heroes. Those who bombed them were cowards."
No person or group had yet claimed responsibility for the convoy attack, officials said. Russian and Syrian military officials said they were not responsible for the attack.
"As an immediate security measure, other convoy movements in Syria have been suspended for the time being pending further assessment of the security situation," Jens Laerke, U.N. humanitarian aid spokesman, told reporters in Geneva. "We remain committed and undeterred to continue to the best of our ability to help all Syrians in need."
It was unclear whether the convoy, loaded with food and 9 tons of items such as antibiotics and trauma kits, had been hit by an airstrike or other form of attack, officials said.
The attack came amid activists' reports of Syrian government airstrikes in a handful of other cities following the end of the cease-fire that began at sundown Sept. 12. The attacks reportedly resulted in multiple civilian casualties, including children.
Syria's military announced Monday that a weeklong cease-fire brokered by the United States and Russia, an ally of President Bashar Assad, was over because of repeated violations by rebels fighters who oppose the government. The opposition also had accused the government of violating the cease-fire.
Russia's Defense Ministry spokesman said the deadly attack was not an airstrike by Russian or Syrian government forces, suggesting instead that it was the work of militants and allies in the area, according to Russian state news agency Tass.
Igor Konashenkov said the Russian military had "carefully studied the video recordings of the so-called activists from the scene and found no signs that any munitions hit the convoy."
Konashenkov said militants from the former Nusra Front, now called Front for the Conquest of Syria, set fire to the convoy, and he questioned why Syrian rescue workers known as "white helmets" happened to be in the area to film the attack.
"Everything shown on the video is the direct consequence of the cargo catching fire ... simultaneously with militants carrying out a massive offensive in Aleppo," Konashenkov said.
Stephen O' Brien, the U.N.'s humanitarian chief, called for an independent investigation of the attack and demanded that those responsible face consequences under international law. He said all parties to the conflict had been notified of the convoy, which was intended to aid 78,000 people and "was clearly marked as humanitarian."
O'Brien said there could be "no explanation or excuse, no reason or rationale for waging war" on humanitarian workers.
"If this callous attack is found to be a deliberate targeting of humanitarians, it would amount to a war crime," he said.
The International Committee of the Red Cross postponed an aid convoy set to deliver supplies to four Syrian towns Tuesday, but spokeswoman Krista Armstrong in Geneva stressed that "it's not a cancellation," just a delay, "so we can get the security guarantees so we can move convoys."
The Syrian Arab Red Crescent suspended aid deliveries Tuesday, but also temporarily, said Stephen Ryan, a spokesman for the International Federation of Red Cross and Red Crescent Societies.
"It's not that humanitarian relief has stopped, it's just that we want to make sure it's safe," Ryan said.
Ryan identified the staff member killed in the attack as Omar Barakat, director of the Syrian Arab Red Crescent's Urem branch.
Attar said Barakat was a "brave member of our family of committed staff and volunteers, working relentlessly to alleviate the suffering of the Syrian people."
The convoy attack threatened already strained U.S.-Russian relations.
U.S. officials expressed outrage, while Russian and Syrian leaders cited prior violations of the cease-fire by U.S. and rebel forces, including Saturday airstrikes on Syrian troops by U.S. coalition warplanes that the Pentagon has called a mistake. More than 60 Syrian troops were killed and dozens wounded.
U.S. State Department spokesman John Kirby faulted Russian and Syrian officials for not allowing humanitarian aid into the country as agreed under the cease-fire even before the attack on the Aleppo convoy, calling it an "egregious violation."
"The destination of this convoy was known to the Syrian regime and the Russian federation and yet these aid workers were killed in their attempt to provide relief to the Syrian people," Kirby said.
Officials had hoped the cease-fire would clear the way for not just aid to beleaguered cities but also the creation of a joint U.S.-Russian military facility in Syria to fight Islamic extremist groups. That seemed unlikely after the convoy attack.
"We don't know if (the agreement) can be salvaged," said a White House official, one of two who briefed reporters on the condition of anonymity on the eve of President Barack Obama's speech to the U.N. General Assembly in New York. "Russia has the burden of demonstrating very quickly their seriousness of purpose ... otherwise, there will be nothing to salvage."
Kremlin spokesman Dmitry Peskov told reporters that there was "little hope" of renewing the cease-fire, faulting American officials who he said, "failed to separate terrorists from the so-called moderate opposition."
But U.S. Secretary of State John F. Kerry insisted that "the cease-fire is not dead."
Kerry met with his Russian counterpart, Sergey Lavrov, and other foreign ministers in the International Syria Support Group as world leaders began their annual gathering at the U.N. General Assembly in New York on Tuesday.
It was a "gloomy" meeting, French Foreign Minister Jean-Marc Ayrault told reporters. But the participants agreed they should do everything possible to salvage the deal brokered by the U.S. and Russia.
"Quite frankly, the Kerry-Lavrov process is the only show in town, and we've got to get that show back on the road," said Boris Johnson, the British foreign secretary.
The U.N. special representative to Syria, Staffan de Mistura, acknowledged that the partial truce was in danger, but said only the U.S. and Russia could declare it over.
Members of the support group _ which includes the U.S. and allies that support some Syrian opposition groups, as well as the Syrian government's allies, Russia and Iran _ plan to meet again Friday to discuss further steps.
Ban singled out Assad's government, which he said continues to barrel bomb neighborhoods and torture thousands of detainees. But he also had harsh words for the "powerful patrons" that he said keep feeding the war machine in Syria.
"Present in this hall today are representatives of governments that have ignored, facilitated, funded, participated in or even planned and carried out atrocities inflicted by all sides of the Syria conflict against Syrian civilians," Ban said.
He appealed to all those with influence over the combatants to get talks started.
