VIDEO: Children among victims of barrel bombs as Aleppo clashes intensify
Dozens of barrel bombs were reported to have fallen on civilian areas of Aleppo as clashes intensified across northern Syria ahead of peace talks due to begin on Wednesday.
A resident told AFP in the aftermath of the bombings, apparently carried out by government helicopters: "Thirty barrel bombs - this is their truce. There are only civilians here, no fighters, no IS jihadists."
With government forces launching air strikes and preparing for an offensive against rebel-held areas in Aleppo, Syria's al-Qaeda affiliate Nusra front and allied rebels pushed offensives around northern, central and coastal Syria on Monday.
The Islamic State (IS) group also took back control of the town of Al-Rai near Turkey, which rival rebels had captured last week, the Syrian Observatory for Human Rights said.
Neither the al-Qaeda-affiliated Nusra Front nor IS are included in a truce brokered by the United States and Russia that came into force on 27 February.
But the fact that rebels are fighting alongside Nusra in such a broad offensive, while government forces push back, suggests that the partial ceasefire has already collapsed in the north of the country.
"Nusra and allied rebel groups are waging three synchronised offensives" on frontlines in Aleppo, Hama and Latakia provinces, Observatory director Rami Abdel Rahman told AFP.
So far, they have seized a hilltop in Latakia province, the heartland of Syrian President Bashar al-Assad's Alawite sect, the group said.
"This is the offensive that Nusra warned it would carry out several weeks ago," Abdel Rahman said.
He was referring to a threat issued by the group when Russian President Vladimir Putin, a key backer of Assad, announced the partial pullout of Russian troops from Syria last month.
A military source confirmed that an offensive was under way.
"Armed groups are trying to attack some military positions in Latakia and Hama provinces, but they have not succeeded in making any advances," the source told AFP on condition of anonymity.
Further north, IS took back the town of Al-Rai, their key supply route from neighbouring Turkey, the Observatory said.
Rebels fighting IS had taken Al-Rai last week following two days of clashes.
"The fact that the rebels could not hold on to Al-Rai shows that it is impossible to maintain an advance against IS without adequate air cover," Abdel Rahman said.
Following the takeover, Turkey's army launched artillery strikes on IS positions, local media reported Monday.
Turkish artillery fired shells from howitzers positioned on its border region of Kilis against IS targets, the private NTV television reported.
Syrian, Russian and US-led coalition warplanes are all staging separate air campaigns in the war-torn country.
The latest violence came ahead of a new round of peace talks in Geneva on 13 April, which will see indirect negotiations between government and opposition delegations.
The UN peace envoy to Syria said on Monday that an upcoming round of negotiations in Geneva would be "crucially important" in finding a solution to the country's brutal five-year war.
In Damascus, de Mistura said the next round of talks would be vital because they would focus on a political transition for Syria, where the fate of President Bashar al-Assad remains a major sticking point.
"We hope and plan to make [the talks] constructive and we plan to make them concrete," de Mistura told reporters after meeting Foreign Minister Walid Muallem.
"We did raise and discuss the importance of protecting and maintaining and supporting the cessation of hostilities which is fragile but is there, and we need to make sure that it continues to be sustained even when there are incidents to be contained," the envoy said.
"Neither Nusra nor IS have an interest in the ceasefire or a peaceful solution to Syria's war - because should the war end, they would no longer have a role," said Syrian Observatory for Human Rights Abdel Rahman.
Clashes around Aleppo on Sunday killed at least 16 pro-government fighters and 19 members of al-Qaeda's affiliate and allied rebel groups, according to the Syrian Observatory for Human Rights.
Inside Aleppo, the Observatory said barrel bomb strikes by government forces on Sunday hit the northeastern neighbourhood of Al-Haidariyah, injuring a number of people including children.
Aleppo, formerly Syria's economic capital, has since 2012 been divided into zones held between rebel groups and areas still under government control.
Syrian opposition figures have warned that the rebellion in Aleppo could be crushed without greater outside support.
"The rebels in Aleppo need the international community to adopt their cause, including providing them with arms and ammunition of all types, logistical support and training troops," said Islam Alloush, a spokesperson for the Jaish al-Islam opposition group.
"The rebels need the international community to present their cause in the international forums and to defend the right of these oppressed people and forcing the foreign militias to leave Syria, and to be serious in fighting terrorists and their ideologies of all forms, as the revolutionary forces did."
He told Middle East Eye that rebel groups would continue to fight alongside Nusra, despite the controversy surrounding the organisation, as long as it was necessary to defeat the Assad forces.
“The recent conflict in Syria divided the military power into two: the regime and its allies, and the opposition with its different groups," he said.
“Taking in consideration the limited resources and weak support, the revolutionary forces in Syria will put its hands with the hands of whoever is willing to fight the regime in Syria, let it be international, regional or local forces. This is what the Syrian agenda dictates over these forces.”