• Syrian army says insurgents entered large parts of Aleppo.
• Says dozens of soldiers killed during insurgent attack
• Russian, Syrian warplanes carry out airstrikes, sources say

The Syrian army said on Saturday dozens of its soldiers had been killed in a major attack by rebels who swept into the city of Aleppo in the northwest, forcing the army to redeploy in the biggest challenge to President Bashar al-Assad in years.

The surprise attack led by the Hayat Tahrir al-Sham has jolted the frontlines of the Syrian civil war that have largely been frozen since 2020, reviving fighting in a corner of the fractured country near the Turkish border. The army said it was preparing a counteroffensive to restore state authority.

Acknowledging the rebel advance, the Syrian army command said insurgents had entered large parts of Aleppo, which had been under full state control since government forces backed by Russia and Iran drove rebels out eight years ago.

Images from Aleppo showed a group of rebel fighters gathered in the city's Saadallah al-Jabiri Square after entering the city overnight, a billboard of Assad looming behind them.

"I am the son of Aleppo, and was displaced from it eight years ago, in 2016. Thank God we just returned. It is an indescribable feeling," said Ali Jumbaa, a rebel fighter, television footage showed.

The Syrian military command said militants had attacked in large numbers and from multiple directions, prompting "our armed forces to carry out a redeployment operation aimed at strengthening the defence lines in order to absorb the attack, preserve the lives of civilians and soldiers, and prepare for a counterattack".

The army said bombardment had stopped the insurgents from establishing fixed positions. It promised to "expel them and restore the control of the state ... over the entire city and its countryside".

Two rebel sources said the insurgents had also captured the city of Maraat al Numan in Idlib province, bringing all of that province under their control, in what would be another significant blow to Assad.

The attack was launched from insurgent-held areas of northwestern Syria that remain outside Assad's grasp.

Two Syrian military sources said that Russian and Syrian warplanes targeted insurgents in an Aleppo suburb on Saturday.

Speaking on Friday, Kremlin spokesperson Dmitry Peskov said Moscow regarded the rebel attack as a violation of Syria's sovereignty. "We are in favour of the Syrian authorities bringing order to the area and restoring constitutional order as soon as possible," he said.

The Syrian Civil Defense, a rescue service operating in opposition-held parts of Syria, said in a post on X that the Syrian government and Russian aircraft carried out airstrikes on residential neighbourhoods, a gas station and a school in rebel-held Idlib, killing four civilians and wounding six others.

The two Syrian military sources said Russia has promised Damascus extra military aid that would start arriving in the next 72 hours. Authorities closed Aleppo airport and roads to the city, the two military sources and a third army source said.

The Syrian army has been told to follow "safe withdrawal" orders from the main areas of the city that the rebels had entered, the three military sources said.

Iran's role in the region

The rebels said on Friday their fighters were sweeping through various Aleppo neighbourhoods.

Mustafa Abdul Jaber, a commander in the Jaish al-Izza rebel brigade, said their speedy advance had been helped by a lack of manpower to support the government in the broader Aleppo province.

Iranian Foreign Minister Abbas Araqchi, in a phone call with his Syrian counterpart on Friday, accused the United States and Israel of being behind the insurgent attack.

The opposition fighters have said the campaign was in response to stepped-up strikes in recent weeks against civilians by the Russian and Syrian air forces on areas of Idlib province, and to preempt any attacks by the Syrian army.

Turkey's foreign ministry said on Friday that the clashes between rebels and government forces had resulted in an undesirable escalation of tensions.

In a statement, spokesperson Oncu Keceli said that avoiding greater instability in the region was Turkey's priority, adding that Ankara had warned that recent attacks on Idlib undermined the spirit and implementation of de-escalation agreements.