Aleppo faces intensified aerial bombardment after Syrian regime and loyalists lose strategic ground, activists say.
More than 500 Syrian civilians have been killed in a single week, mostly in government and Russian air raids and shelling, across several cities in the war-torn country.
Casualty figures released on Saturday by the Local Coordination Committees (LCC), a grassroots network of activists in Syria, recorded 508 civilians killed between August 13 and August 19, including 96 children and 73 women.
Most of the deaths occurred in Russian and Syrian aerial bombardment across Aleppo, Idlib, Damascus, and Hama, according to the LCC.
In the northern Syrian city of Aleppo and its suburbs, at least 205 of the total 508 were killed in shelling of the city’s previously-besieged eastern neighbourhoods, and in clashes with Assad forces in the battle to break the siege. Deaths were also reported from landmines left by the Islamic State of Iraq and the Levant (ISIL) group around the town of Manbij.
Moataz Hamouda, an Aleppo-based activist with the LCC, said civilian deaths have increased as the Assad regime has lost ground.
"Russia is responding to its military defeats on Aleppo’s fronts after the strong blow that the rebels dealt to government loyalists," Hamouda told Al Jazeera, referring to the breaking of the Aleppo siege.
"The breaking of the city’s siege and the takeover of military forts by rebels has also frustrated Syria and Russia," he said.
"They have also frantically increased their use of banned weapons - from cluster missiles to white phosphorous and napalm."
Numerous reports have emerged in recent days of Syrian government forces using cluster munitions, which are banned by more than 100 countries due to the weapon’s indiscriminate targeting and risks posed to civilians.
Once Syria’s largest city, Aleppo has been divided between opposition control in the eastern half, and government control in the west since mid-2012. Government forces launched an offensive to retake the rebel-held half of the city, imposing a month-long siege that was eventually broken.
"Civilians fear the warplanes"
The LCC also recorded the killing of 93 civilians in Idlib, 52 in Homs, 51 in Damascus, 38 in Deir Ezzor, and 34 in Hama, with the majority being killed in air raids and fighting involving forces loyal to Syrian President Bashar al-Assad, backed by Russian and Iranian forces.
Residential areas, mosques and markets are being increasingly hit, said Zouhir al-Shimale, a local journalist and resident of Aleppo.
"Apart from the daily targeting of Aleppo’s neighbourhoods with cluster bombs in an unprecedented way, tens of activists and civilians have been killed and injured in recent days," Shimale told Al Jazeera.
"This is causing a large exodus from the city, from Aleppo’s liberated neighbourhoods in the eastern half, to the suburbs, and to Turkey as well, in spite of the availability of food supplies," he said.
"Civilians fear the warplanes that are always in the sky."
Shimale said that close to half of the city’s residents are estimated to have left the city amid the ongoing aerial bombardment of main roads and residential areas.
Staffan de Mistura, United Nations special envoy to Syria, called for a 48-hour truce around Aleppo last week, to allow for aid deliveries and medical evacuations.
Ibrahim al-Hajj, media centre director in Aleppo for the Syrian Civil Defence, a volunteer rescue group also known as the White Helmets, said the Syrian government’s recent loss of strategic areas in the besieged city, particularly al-Ramosa and the artillery school, had prompted the escalation in attacks.
"Russia and the Syrian regime have been targeting civilians and residential areas the most," Hajj said.
"They want to free the area of civilians and coerce them into leaving so that they can bomb their targets freely."
A coalition of rebels calling themselves the Army of Conquest claimed to have captured a strategic military base as well as an armament school and an artillery school in the al-Ramosa quarter of Aleppo earlier this month. The rebels reportedly then used the captured base to launch their offensive to break the regime’s siege of Aleppo.
The Syrian conflict began as a mostly unarmed uprising against Assad in March 2011, but quickly escalated into a full-blown civil war.
Monitoring groups estimate that more than 280,000 Syrians have been killed throughout the five years of bloodshed and millions displaced.