The Syrian government has launched fresh air strikes across Aleppo as part of its ongoing offensive against rebel groups in the historic city, as John Kerry, the United States secretary of state, plans to head to Geneva in an attempt to revamp peace talks.
Government forces carried out at least six air strikes targeting the residential areas of al-Lairamon and Kafr Hamra on Sunday morning, Zouhir Al Shimale, a local journalist, said.
"Late last night, there was shelling on a big basement storing relief aid and food," he told Al Jazeera. "Most of it was burned."
|Aleppo reels after raids by government and Russian allies
The US on Saturday demanded that Syrian President Bashar al-Assad's forces halt their bombardment of Aleppo and help restore a nationwide ceasefire.
Aleppo was left out of a temporary US-Russian brokered truce that appeared to be holding in the government stronghold of Latakia as well as Damascus and the nearby rebel bastion of Eastern Ghouta.
The Russian defence ministry said on Sunday that the temporary "calm" was extended for another 24 hours, as the Latakia one was set to stay in place for 48 more hours.
Terrified residents fled a new wave of air strikes on rebel-held areas of the divided city as Russia, a close ally of Damascus, said it would not pressure the Assad government to halt its air strikes.
With the peace process hanging by a thread, Kerry was to fly to Geneva on Sunday for talks with UN envoy Staffan de Mistura and the Saudi and Jordanian foreign ministers.
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In calls to de Mistura and the lead Syrian opposition negotiator, Kerry expressed "deep concern" about Aleppo, which has suffered some of the worst fighting in a conflict that has killed more than 270,000 people and displaced millions.
"The secretary made clear that we urged Russia to take steps to stop government violations, especially its indiscriminate aerial attacks in Aleppo," a state department spokesperson said.
A new round of United Nations-backed peace talks is set to start on May 10 in Geneva.
|Homes, medical facilities and other buildings across the city have been hit hard by air strikes and shells [Al Jazeera]
"The situation has become unbearable," Abu Mohammed, a resident of the battered Bustan al-Qasr neighbourhood, told AFP as he prepared to flee with his wife and five children. "Everything is paralysed."
Russia said that it would not ask Damascus to halt air raids on Aleppo.
"No, we are not going to put pressure on [Damascus] because one must understand that the situation in Aleppo is part of this fight against the terrorist threat," Gennady Gatilov, Russia's deputy foreign minister, said.
At least 246 civilians have died in shelling, rocket fire and air strikes in both sides of the city since April 22, the Syrian Observatory for Human Rights said.
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At least 10 civilians died in rebel-controlled areas on Saturday, according to the civil defence.
The violence in Aleppo has severely tested the February 27 truce between the government and rebels intended to pave the way to an end to the five-year conflict..
|The rebel-held eastern part of the city has sustained massive damage during the bombing campaign [Al Jazeera]
The SANA state news agency on Saturday said shelling of western government-held neighbourhoods killed three civilians, including a child, and blamed al-Qaeda affiliate al-Nusra Front and its allies.
A pro-government newspaper said on Thursday that the army was preparing an offensive to recapture all of Aleppo and the surrounding province.
Anas al-Abdeh, head of the Istanbul-based opposition National Coalition, on Saturday accused the government of "war crimes and crimes against humanity" in Aleppo.
Human Rights Watch also said air strikes on medical facilities in the city "may amount to war crimes".
Qatar called for an emergency Arab League meeting, and Saudi Arabia also condemned the government strikes.
|Many civilians have fled Aleppo, while others have taken refuge in their homes in order to avoid strikes [Al Jazeera]
Source: Al Jazeera and agencies