BEIRUT: Syrian rebels announced Sunday night the start of the battle to “liberate” Aleppo, a day after they breached a month-old siege imposed by regime and Hezbollah forces on the rebel-held eastern Aleppo. Hours before Jaish al-Fatah declared the assault, the rebels came under intense air attack from pro-regime forces trying to repel the advance that also cut government-held Aleppo’s supply route. “We announce the start of a new phase to liberate all of Aleppo,” Jaish al-Fatah said in a statement posted online. Rebels have taken most of a large government military complex southwest of Aleppo city in a major offensive begun Friday to break a monthlong siege and are now attacking further into government-held territory.

The surprise advance in Ramouseh allowed fighters from rebel areas in western Syria to break through a strip of government-controlled territory Saturday and connect with fighters in the encircled sector of eastern Aleppo.

But fierce fighting and continuous Russian and Syrian airstrikes in and around the Ramouseh area mean no safe passage for besieged eastern Aleppo residents has been established, activists and the Syrian Observatory for Human Rights said.

Syrian President Bashar Assad wants to take full control of Aleppo, prewar Syria’s most populous city, which has been divided between rebel- and government-held areas.

Assad’s regime forces are supported in Syria by Russian air power, Iranian militias and fighters from Lebanon’s Hezbollah, which, according to Lebanese security sources, sent reinforcements to Aleppo. The sources added that eight Hezbollah fighters were killed in battle.

The sources added that the Iraqi Shiite militia, Harakat al-Nujbaa, has also sent reinforcements to support the regime in Aleppo.

Rebel gains this weekend could change the balance of power in Aleppo, after Assad said a siege by government and allied forces on rebel-held eastern Aleppo in early July was a prelude to retaking the city. The loss of Aleppo would be a crushing blow for rebels.

“We have now seized full control of the Ramouseh area. ... We are in our trenches but there are insane airstrikes of unprecedented ferociousness. The regime is using cluster and vacuum bombs,” said Abu al-Hasanein, a senior commander in Fatah Halab, the coalition of moderate rebel groups inside the city.

Pro-Syrian government news channels have mostly played down the rebel gains and say Syrian army efforts have caused rebels to withdraw from some recently gained areas. But Lebanese pro-Syrian government news channel Al-Mayadeen said late Saturday the Syrian army had “withdrawn from a number of positions southwest of Aleppo and repositioned itself in new defensive lines.”

The media arm of Hezbollah said airstrikes leveled one of the military colleges after forces withdrew.

As the rebels took over parts of the Ramouseh military complex, which contains a number of military colleges, they broadcast images of the weaponry and ammunition they were taking possession of.

Jabhat Fatah al-Sham, formerly the Al-Qaeda-affiliated Nusra Front, posted pictures of rows of armored vehicles, munitions, howitzers, rockets and trucks.

“The turning point was the fall of the artillery school,” said Islam Alloush, spokesman for the Army of Islam rebel group and a former Syrian army officer. Alloush said the rebel groups put massive efforts and ammunition into the battle, adding that his group – the strongest near Damascus – had mobilized fighters from five neighboring provinces to take part.

The rebel front line is now pushing northwest into regime-held Aleppo on the edges of the Hamdanieh neighborhood and a housing estate called the 3,000 project, rebels and the Observatory said. North of Hamdanieh in the direction of the rebels’ push is another large government military complex, the Assad military engineering academy. The opposition Syrian National Coalition congratulated rebels on making “spectacular gains [which send] a clear message to the Assad regime, Iran and Russia that they will not be able to defeat the Syrian people or dictate the terms of a settlement.” Fears are growing in government-held western Aleppo that it might become besieged by rebels, as east Aleppo has been by government forces, because the main route south to Damascus for goods transport, the Ramouseh road, has been severed.

State television said Sunday: “Our forces have redeployed after absorbing the attack of thousands of mercenaries, and the army has found a new route to allow food and gas” into western Aleppo.

News of the rebel advance caused food prices to rise by as much as four times in western Aleppo, the Observatory said.

“Unfortunately, after the road was cut, the price of a loaf of bread immediately shot up from 200 to 800 Syrian pounds,” said Walaa Hariri, a 48-year-old mother of three from the Furqan district.

Following the cutting of the main Ramouseh road, Observatory director Rami Abdel-Rahman told Reuters that military vehicles can still get in and out of western Aleppo through remaining exit roads to the north, but these are not safe enough for civilians.

In eastern Aleppo, despite some scenes of celebration as fighters broke the siege yesterday, the lack of a safe route out means conditions for residents remain unchanged. Three vans of vegetables crossed into eastern Aleppo, Abdel-Rahman said, but this was a symbolic gesture and the corridor was too dangerous for civilians or significant supplies to pass.

The U.N. and humanitarian agencies have said conditions in rebel-held eastern Aleppo have become very concerning. With agencies