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Syria rebels in bitter battle for territory in Aleppo

Narciso Contreras / AP

A rebel sniper aims at Syrian army positions in Aleppo's Jedida district on Oct. 29, 2012.

Narciso Contreras / AP

A rebel fighter belonging to the Qatebee Sokor Al-Islam group runs for cover as a Syrian army tank shells the rebel position during clashes in the Jedida district of Aleppo on Oct. 29, 2012.

Narciso Contreras / AP

An apartment destroyed by tank shelling in the Karm al-Jabel neighborhood of Aleppo after several days of intense clashes between rebel fighters and the Syrian army, Oct. 28, 2012.

Narciso Contreras / AP

A rebel fighter belonging to the Liwa Al-Tawhid group kisses a Quran as mortar explosions and gunshots are heard in the nearby battlefield in the Karm al-Jabel neighborhood of Aleppo on Oct. 28, 2012.

Javier Manzano / AFP - Getty Images

A rebel fighter looks at smoke billowing from a bus that caught on fire after a regime sniper allegedly shot at it in Aleppo on Oct. 28, 2012.

The conflict in Syria intensified on Monday with scores of airstrikes that anti-regime activists called the most widespread bombing in a single day since Syria's troubles started 19 months ago, The Associated Press reports.

On Tuesday, Syrian warplanes bombed rebel positions on the outskirts of the central city of Homs to try to break a siege of an army base housing dozens of soldiers, opposition activists said. 

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