Hundreds of civilians are fleeing Syria's second-largest city, Aleppo, after rebel Islamist forces took over parts of it.
The Syrian army says dozens of its soldiers have been killed in a major attack by rebels who swept into the city, forcing the army to redeploy in the biggest challenge to President Bashar al-Assad in years.
The surprise attack, led by the Islamist group Hayat Tahrir al-Sham, was the boldest rebel assault for years in a civil war where front lines had largely been frozen since 2020.
The war, which has killed hundreds of thousands of people and displaced many millions, has ground on since 2011 with no formal end, although most major fighting halted years ago after Iran and Russia helped Mr Assad's government win control of most land and all major cities.
In Aleppo, Russian warplanes allied with the Syrian government are targeting rebel supply lines on the city's edge, with independent war monitor the Syrian Observatory for Human Rights saying about 20 fighters had been killed in air strikes on rebel reinforcements.
Aleppo had been firmly held by the government since a 2016 victory there — one of the war's major turning points — when Russian-backed Syrian forces besieged and lay waste to rebel-held eastern areas of what had been the country's largest city.
"I am a 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 Jumaa, a rebel fighter, in television footage filmed inside the city.
Acknowledging the rebel advance, the Syrian army command said insurgents had entered large parts of Aleppo.
After the army said it was preparing a counterattack, air strikes targeted rebel gatherings and convoys in the city, the pro-Damascus newspaper al-Watan reported.
One strike caused casualties in Aleppo's Basel square, a resident told Reuters.
Images filmed on Saturday showed people posing for photos on a toppled statue of Bassel al-Assad, late brother of the president.
Fighters zipped around the city in flatback trucks and milled around in the streets.
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".
The rebels also took control of Aleppo airport, according to a statement by its operations room and a security source.
With Mr Assad backed by Russia and Iran, and Türkiye supporting some of the rebels in the north-west where it maintains troops, the offensive has brought into focus the conflict's knotted geopolitics.
Fighting in the north-west had largely abated since Türkiye and Russia reached a de-escalation agreement in 2020.
Russian and Turkish ministers talk
Russian Foreign Minister Sergei Lavrov held a phone call with his Turkish counterpart, Hakan Fidan, discussing the situation in Syria, the Russian Foreign Ministry said on Saturday, local time.
"Both sides expressed serious concerns at the dangerous development of the situation," the ministry said.
They agreed that it was necessary to coordinate joint actions to stabilise the situation in the country.
Turkish security officials had said on Thursday that Ankara had prevented operations that opposition groups wanted to organise, in order to avoid further tensions in the region.
Iranian Foreign Minister Abbas Araqchi told Mr Lavrov in a phone call that the rebel attacks were part of an Israeli-US plan to destabilise the region, Iranian state media said.
Russian aircraft striking residential areas, White Helmets
The Syrian Civil Defense, a rescue service better known as the White Helmets operating in opposition-held parts of Syria, said in a post on X that Syrian government and Russian aircraft carried out air strikes on residential neighbourhoods in rebel-held Idlib, killing four civilians and wounding six others.
Two Syrian military sources said Russia had promised Damascus extra military aid that would start arriving in the next 72 hours.
The Kurdish People's Protection Units (YPG), which spearhead the US-backed Syrian Democratic Forces that control much of north-eastern and eastern Syria and have long had a foothold in Aleppo, widened their control in the city as government troops left, a senior YPG source said.
Mustafa Abdul Jaber, a commander in the Jaish al-Izza rebel brigade, said the rebels' speedy advance had been helped by a lack of Iran-backed manpower to support the government in the broader Aleppo province.
Iran's allies in the region have suffered a series of blows at the hands of Israel as the Gaza war has expanded through the Middle East.
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 pre-empt any attacks by the Syrian army.
Insurgents use social media to show off territorial gains
In a social media post, a number of insurgents were pictured outside the Aleppo citadel, a medieval palace in the old city centre which is one of the largest in the world.
The rebels also posted mobile phone videos of themselves speaking to residents in their homes, seeking to reassure them they will cause no harm.
State media, however, referring to the fighters as terrorists, said a number of them had been chased and arrested by government troops after posing for pictures near city landmarks.
On a state TV morning show, commentators on Saturday said army reinforcements and Russia's assistance will eventually repel the insurgents, blaming Türkiye for supporting their push into the Aleppo and Idlib provinces.
Russia's state news agency Tass also quoted Oleg Ignasyuk, a Russian defence ministry official coordinating in Syria, as saying Russian planes had targeted and killed 200 militants taking part in the offensive on Friday. It provided no further details.
Rebel attack follows weeks of simmering tension
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 battle for Aleppo was a turning point in the country's long-running civil war, which began in 2011 following protests against Bashar al-Assad's rule.
The latest rebel attack on Aleppo followed weeks of simmering low-level violence, including government attacks on opposition-held areas.
Türkiye, 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 rebel offensive came as Iran-linked groups backing the Assad regime, primarily Lebanon's Hezbollah, have been preoccupied with their own battles at home.
A ceasefire in Hezbollah's two-month war with Israel took effect on Wednesday, the day the Syrian opposition factions announced their offensive. Israel has also escalated its attacks against Hezbollah and Iran-linked targets in Syria over the past 70 days.
ABC/wires
