Insurgents broke through government defense lines in Aleppo on Friday and entered the city’s western neighborhood with little resistance. The insurgents launched their shock offensive in Aleppo and Idlib countryside on Wednesday and wrestled control of dozens of villages and towns along the way, including a strategic town south of Aleppo.

The pro-government Al-Watan newspaper reported airstrikes on the edge of Aleppo city, targeting rebel supply lines. It posted a video of a missile landing on a gathering of fighters and vehicles, in a street lined with trees and buildings.

Twenty fighters were killed in the airstrikes that targeted rebel reinforcements, said the Syrian Observatory for Human Rights, which monitors the country’s unresolved civil war. Aleppo residents reported clashes and gunfire, and some were fleeing the fighting.

Schools and government offices were closed Saturday as most people stayed indoors, according to Sham FM radio, a Syrian station. Bakeries were open.

In social media post, the insurgents were pictured outside of Aleppo citadel, the medieval palace in the old city center, and one of the largest in the world.

State media reported that a number of “terrorists," including sleeper cells, have infiltrated parts of the city. Government troops chased them and arrested a number who posed for pictures near city landmarks, state media said.

On a state TV morning show Saturday, commentators said army reinforcements and Russia’s assistance will repel the “terrorist groups,” blaming Turkey for supporting the insurgents' push into Aleppo and Idlib provinces.

Russia’s state news agency Tass quoted Oleg Ignasyuk, a Russian Defense Ministry official coordinating in Syria, as saying that Russian warplanes targeted and killed 200 militants who launched the offensive in the northwest on Friday. It provided no further details.

Aleppo has not been attacked by opposition forces since they were ousted from eastern neighbourhoods in 2016 following a gruelling military campaign in which Syrian government forces were backed by Russia, Iran and its allied groups.

The attack on Aleppo followed weeks of simmering low-level violence, including government attacks on opposition-held areas. Turkey, which has backed Syrian opposition groups, failed in its diplomatic efforts to prevent the Syrian government attacks, which were seen as a violation of a 2019 agreement sponsored by Russia, Turkey and Iran to freeze the line of the conflict.

The offensive came as Lebanon’s Hezbollah, which has backed Syrian government forces since 2015, has been preoccupied with the Israeli assault on Lebanon. A ceasefire in the two-month escalation and year-long war Israeli took effect Wednesday, the day Syrian factions announced their offensive. Israel has also escalated its attacks in Syria during the last 70 days.

Turkey’s state-run Anadolu news agency said the insurgents have seized control of large parts of Aleppo and Idlib countryside.

The 2016 battle for Aleppo was a turning point in the war between Syrian government forces and rebel militants after 2011 protests against President Bashar Assad’s rule turned into an all-out war.