At least four people have been killed as rebel groups launched attacks on Aleppo for the first time in years, Syrian state media reported, as the rebel forces ramped up their assault on government-held positions in the country’s northwest.

The rebels launched a ground attack on the city of Aleppo after blowing up two car bombs on Friday, and were clashing with government forces on the city’s western edge, according to a Syria war monitor and fighters.

The Turkish state news agency Anadolu reported that the armed groups had entered Aleppo city centre, without providing further details.

The Syrian army said on Friday it repelled a major offensive on the city.

“Our forces continue to repel the major offensive launched by armed terrorist groups,” the army said in a statement, adding that it was “able to retake control of certain positions”.

Earlier, four civilians including two students were killed when rebel groups shelled a building housing university students on Friday, the state news agency SANA reported.

Rebels led by the Hay’et Tahrir al-Shams armed group on Wednesday launched an offensive, capturing a dozen towns and villages in the northwestern province of Aleppo.

The assault is the most intense fighting in northwestern Syria since 2020, when government forces seized areas previously controlled by opposition fighters, and has come after weeks of low-simmering violence.

Russian and Syrian warplanes bombed rebel-held areas northwest Syria near the border with Turkiye on Thursday to try to push back the offensive that had captured territory for the first time in years, Syrian army and rebel sources said.

Reporting from Hatay, Turkiye, Al Jazeera’s Sinem Koseoglu said that opposition sources say they have seized control of more than 47 villages.

“They have taken control of the countryside of Western Aleppo. But of course, they are close to the city centre of Aleppo… Also the opposition factions took control of the M5 highway which is a very strong logistics and military transfer route,” she said.

“Given the situation in southern Lebanon, the opposition saw an opportunity to gain back these places from the Syrian government,” she added.

The United Nations Office for the Coordination of Humanitarian Affairs said “more than 14,000 people – nearly half are children – have been displaced” by the violence.

Colin Clarke, senior research fellow at The Soufan Center, told Al Jazeera that this violence is just really a reflection of how divided Syria is right now.

He said he doesn’t expect the rebel fighters to push past north west Syria.

“They’re contained to kind of control Idlib, Aleppo… I think they have their hands full in governing the current territory. I wouldn’t expect them to push much more beyond North Western Syria at the moment,” he said.

Aleppo resident Sarmad, 51, told AFP he could hear “the sounds of missiles and artillery shelling around the clock”.

“We’re scared that war will break out and we’ll be displaced from our homes again,” he said.

Syria’s civil war began when President Bashar al-Assad’s forces cracked down in 2011 on pro-democracy protests.

Over the years, the conflict has morphed into a complex war drawing in foreign powers, including al-Assad’s allies Russia, Iran and the Lebanese armed group Hezbollah.

Iranian Foreign Minister Abbas Araghchi “stressed Iran’s continued support for the government, nation and army of Syria in their fight against terrorism,” during a phone call with his Syrian counterpart Bassam al-Sabbagh, according to a statement on Friday.

“The Iranians are overwhelmed. You know what once was this grand project, put forth by Suleimani…you know this axis of resistance, this desire to establish a so called Shia crescent, has now crumbled over the past year…so in Tehran there is a lot of concern over the geopolitical developments,” Clark noted.

Kremlin spokesperson Dmitry Peskov described the situation in Aleppo as “an infringement on the sovereignty of Syria.”

He expressed support for “the government of Syria to quickly restore order in this district and restore the constitutional order”.

Asked about unconfirmed Russian Telegram reports that al-Assad had flown into Moscow for talks with Russian President Vladimir Putin, Peskov said he had “nothing to say” on the matter.

Moreover, the Turkish foreign ministry has demanded an end to strikes on Syria’s rebel enclave Idlib, in a statement.

“It is of utmost importance for Turkiye that yet another and greater instability is avoided and that civilians are not harmed.”