(CBS/AP) BEIRUT - Fighting in Syria's largest city of Aleppo stretched into its 11th day on Tuesday amid growing international condemnation of the Syrian government's crackdown on a tenacious rebellion that has lasted 17 months.
Activists reported renewed bombardments of rebel-held neighborhoods and clashes in many parts of Aleppo as the army pushed on with its offensive to retake this key northern city.
The battle for Aleppo, Syria's commercial hub with around 3 million inhabitants, has now lasted longer than the rebel assault on the capital Damascus that regime troops crushed earlier in July.
Despite regime claims of success and repeated forays by tanks and ground forces into rebel-controlled areas in the northeast and southwest of the city, the rebels appear to have held their ground, prompting government forces to resort to more shelling by artillery and mortars. Rebel positions are also being attacked with helicopter gunships.
The U.N. has estimated that 200,000 people have fled the fighting, either taking shelter in nearby villages or making the trek to the refugee camps across the border in Turkey.
Refugees from Aleppo have described a city devastated by shelling and wracked by food shortages.
The Britain-based Syrian Observatory for Human Rights said the rebel bastion of Sakhour in the northeast of Aleppo was being shelled and that clashes had broken out between rebels and government forces elsewhere in the city, especially in Salaheddine in the southwest.
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Syria's government claims gains in Aleppo
This image from amateur video purports to show Free Syrian Army soldiers standing near a captured tank in Anadan, 10 miles from Aleppo, Syria, July 30, 2012.
(Credit: AP/Ugarit News via AP video)D'Agata reported this morning that rebels said a series of explosions heard in the area was the captured tanks being used against the Syrian army.
Video: Syrian rebels score victory NW of Aleppo
Rebels forces also claim to have taken the town of al-Bab in Aleppo province. A video posted online by activists Sunday showed rebels riding through the town in a captured regime tank.
"Rebels have completely seized control of the town of al-Bab east of Aleppo. It is the biggest town in the Aleppo countryside," said local activist Mohammed Saeed. He added that another 200 fighters had entered the city Sunday to join the 1,000 fighters who had poured into the city over the past few days to repel the Syrian army's effort to regain control.
Meanwhile, Turkey has increased its military presence along its border on Tuesday. AP Television spotted several tanks that had been deployed to Kilis province, which sits along the 564-miles frontier shared between the two countries.
A Syrian girl carries bags of pita bread as people line up outside a bakery in the northern town of Aldana, near Aleppo, on July 31, 2012. Fighting raged in Syria's commercial capital for a fourth straight day.
(Credit: AHMAD GHARABLI/AFP/Getty Images)In addition to Turkey, Jordan, Iraq and Lebanon are also facing the problem of Syrian refugees.
The U.N. refugee agency said it has been unable to reach all 200,000 people fleeing the fighting in Aleppo, Syria's largest city.
