The rebel Free Syrian Army on Thursday withdrew completely from the embattled district of Salaheddin, in the northern city of Aleppo, a rebel commander said.
“We have staged a tactical withdrawal from Salaheddin,” the commander, Wassel Ayub, told AFP by phone. “The district is completely empty of rebel fighters. Regime forces are now advancing into Salaheddin.”
Troops battled rebels in central Aleppo Thursday a day after launching a ground offensive backed by air power for control of the commercial capital, a strategic prize in Syria's nearly 17-month uprising.
Day two of the most significant ground attack in Aleppo came as Syria's key regional ally Iran prepared to host a meeting aimed at finding ways to end the raging conflict.
The Syrian Observatory for Human Rights reported an intense bombardment of the Hanano, Saif al-Dawla, Shaar and Sakhur districts of Aleppo from 3:00 a.m (local time).
It also reported the deployment of regime reinforcements, saying several hundred soldiers, three more tanks and troop transports arrived early in the morning.
The Local Coordination Committees, a network of opposition activists on the ground, said gunfire was also heard in several suburbs of the northern city, with shelling focused on opposition bastion of Saleheddine and a northeast district and areas in the city's southwest.
At least 105 people have been killed across Syria on Thursday by security force gunfire, the Syrian Network for Human Rights reported, according to Al Arabiya.
Backed by heavy armor and air power, forces loyal to President Bashar al-Assad launched a major ground offensive on Wednesday against the rebels who had claimed to have control of half of the city.
Damascus said its troops had retaken the key Salaheddin district, but the insurgents said they had recaptured much of what they had lost.
Rebel commander Wassel Ayub of the Free Syrian Army said the FSA had launched a counter-attack and retaken part of Salaheddin.
"For an hour and a half, the Free Syrian Army has staged a counter-attack and reclaimed three streets out of five seized by regime forces," he told AFP by telephone.
"We staged our counter-attack after 700 fighters arrived from the southern neighbourhood of Sukari, Bustan al-Qasr, Shaar and Hanano" in the east.
On Tuesday, Assad vowed to crush the rebellion that erupted in March 2011.
"The Syrian people and their government are determined to purge the country of terrorists and to fight the terrorists without respite," he was quoted by state media as telling a visiting Iranian envoy, using his regime's term for rebels.
Tehran is due to host a meeting later on Thursday aimed at finding ways to end the conflict. But participation was looking thin, with no government confirming its foreign minister will be taking part.
Syria itself will not be represented, according to a foreign ministry source in Damascus. The Russian Foreign Ministry on Wednesday announced its ambassador to Iran would attend “if the meeting in Tehran really takes place.”
Iranian Foreign Minister Ali Akbar Salehi said Tehran was attempting to revive parts of former international envoy Kofi Annan's plan, notably: implementing a ceasefire, sending humanitarian aid, and laying groundwork for national dialogue.
Only those governments with a "realistic position" on Syria were invited, Iran's foreign ministry said, implying countries which shared Tehran's position.
On Tuesday, Jordan's King Abdullah II said Assad might make a "worst case scenario" retreat to an Alawite stronghold in the predominantly Sunni Muslim country if he falls.
"I have a feeling that if he can't rule Greater Syria, then maybe an Alawi enclave is Plan B," Abdullah told US television network CBS, referring to the offshoot sect of Shiite Islam to which Assad belongs.
Jordan is currently hosting more than 150,000 Syrians, many of them in temporary residences in Ramtha across the border from Daraa, cradle of the revolution in southern Syria.
The Jordanian authorities have started transferring some of the refugees to a new seven-square-kilometer camp at Zaatari, which the United Nations says can take up to 120,000 people.
The UN refugee agency estimates that 276,000 Syrians have fled, mainly to Jordan, Turkey and Lebanon, from a conflict that activists say has claimed more than 21,000 lives.