At least 955 civilians, including 219 children, have been killed in fighting in Syria's northern city of Aleppo over the past three months, a monitoring group reported Friday.
The victims have been killed in tit-for-tat attacks by regime forces and opposition rebels in eastern Aleppo city since April 22 when violence in the city escalated, according to Britain-based Syrian Observatory for Human Rights.
The dead included 563 people killed in airstrikes and shelling by the regime on the city's rebel-held areas, the watchdog said.
Retaliatory shelling attacks by opposition forces on regime-controlled areas in Aleppo during the same period left at least 356 civilians dead, according to the Observatory, which relies on a network of activists inside war-torn Syria.
The watchdog added that 23 other people were killed by rebel shelling on the Kurd-held neighborhood of Sheikh Maksoud in the northern section of Aleppo.
Thirteen more people were killed in other incidents of violence in the city.
On Sunday, regime forces took control of Castello Road, the only supply route into rebel-held areas in eastern Aleppo, raising fears about a humanitarian crisis for thousands of residents there.
Once Syria's commercial hub, Aleppo has been divided between the forces of Syrian President Bashar al-Assad in the west and rebels in the east since fighting erupted for control of the city in mid-2012.
Meanwhile, Human Rights Watch (HRW) called Friday on the Syrian government and its allies to allow aid access to besieged parts of Aleppo.
"Syrian government forces are repeating the terrible siege tactics in densely populated eastern Aleppo that devastated civilian populations in other towns in Syria," said Nadim Houry, deputy Middle East director at HRW.
"Syrian authorities should allow aid in and permit civilians wishing to leave to do so safely," he added.
The UN estimates that the eastern part of Aleppo city has a population of between 250,000 to 300,000, and aid agencies estimate that a third of them depend on aid delivered via the Castello Road.
International aid workers told HRW that residents could face health problems within two weeks without proper nutrition, but it has been three weeks since aid has been delivered to the city.
Separately, the Observatory said a tunnel blast under a regime position in Aleppo on Thursday killed 38 government soldiers.
The monitor had earlier reported a toll of 14 in the blast.
Footage posted online by the Thuwwar al-Sham, an opposition rebel group, showed a massive blast destroying a multi-storey building.
Elsewhere, regime forces backed by the Lebanese Shiite movement Hezbollah took control of the rebel-held village of Herera in Wadi Barada in the northwestern countryside of Damascus, the Observatory said.