A monitor of Syria's war said Saturday jihadist rebels now control a majority of Aleppo city, reporting Russian air strikes on parts of Syria's second city for the first time since 2016.
"Hayat Tahrir al-Sham (HTS) and allied factions... took control of most of the city and government centres and prisons", said the Britain-based Syrian Observatory for Human Rights, referring to a jihadist alliance led by Al-Qaeda's former Syria branch.
Syrian jihadist rebels have pressed a lightning offensive against forces of the Iranian- and Russian-backed Syrian government since Wednesday, the same day a fragile ceasefire took effect in neighbouring Lebanon between Israel and Iran-backed militant group Hezbollah after two months of all-out war.
Overnight, Russian "warplanes launched raids on areas of Aleppo city for the first time since 2016", added the Britain-based Observatory, which relies on a network of sources inside Syria.
It raised the death toll in days of clashes to 311 -- 183 from HTS and allied Turkish-backed factions, 100 soldiers and pro-government forces, as well as 28 civilians.
State media reported that four civilians were killed when HTS shelled a student residence in Aleppo.
Iran-backed militias have a heavy presence in the Aleppo region after providing crucial ground support when the Syrian army -- backed by Russian air power -- recaptured rebel-held areas of the city in 2016.
The Observatory said that "the governor of Aleppo and the police and security branch commanders withdrew from the city centre".
The overnight air strikes coincided with "the arrival of large (rebel) military reinforcements" to the area, the Observatory added.