audio, stills, text and or video: Go to http://www.zReportage.com to see more - Tens of thousands of Syrians have lost their lives in ther escalating conflict between forces loyal to Bashar as-Assad and those opposed to his rule. Over the past month, rebel forces in Syria have enjoyed tactical successes which analysts say demonstrate their growing ability to challenge the government's military dominance. The rebels have displayed military strength and organisation in capturing several major military bases, seizing weaponry, disrupting supply lines, and forcing the military to pull back. The 20-month-old conflict that has killed 40,000 people has become house-by-house, street-by-street urban warfare with rebels dodging snipers and climbing and crawling through holes in destroyed structures for safety. There are concerns that Assad's desperation could result in a chemical weapons attack. U.S. intelligence showed that the government is filling aerial bombs with sarin gas at two locations near military airfields. Syria has said it wouldn't use chemical weapons, 'even if it had them, against its own people.'
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Dec. 5, 2012 - Aleppo, Syria - A Free Syrian Army soldier stands in the Bustan Al-Pasha neighborhood.
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Nov. 18, 2012 - Aleppo, Syria - A Free Syrian Army fighter mans a sniper position.
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Nov. 18, 2012 - Aleppo, Syria - The view through a sniper hole in the Old City.
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Nov. 18, 2012 - Aleppo, Syria - A Free Syrian Army fighter in the Kadi Askar cemetery stands where a bomb exploded six days ago.
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Nov. 18, 2012 - Aleppo, Syria - A Free Syrian Army fighter checks on a sniper position in the Old City.
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Nov. 19, 2012 - Aleppo, Syria - Free Syrian Army fighters in Al-Amryia neighborhood.
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Nov. 19, 2012 - Aleppo, Syria - Free Syrian Army fighters in Al-Amryia neighborhood.
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Nov. 19, 2012 - Aleppo, Syria - Free Syrian Army fighters in Al-Amryia neighborhood.
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Nov. 29, 2012 - Aleppo, Syria - A Free Syrian Army fighter in Al Amryia neighborhood.
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Nov. 20, 2012 - Aleppo, Syria - Free Syrian Army fighters keep watch in the Karm al Jabal neighborhood.
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Nov. 21, 2012 - Aleppo, Syria - A Free Syrian Army fighter fires his AK-47.
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Nov. 21, 2012 - Aleppo, Aleppo, Syria - A Free Syrian Army fighter loads a machine gun.
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Nov. 21, 2012 - Aleppo, Aleppo, Syria - Destroyed street in Karm al Jabal neighborhood in Aleppo.
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Nov. 23, 2012 - Aleppo, Syria - Fighters of the Free Syrian Army dig a hole to bury a comrade killed yesterday by a sniper in Al Amryia.
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Nov. 23, 2012 - Aleppo, Syria - A Free Syrian Army fighter, 23, who was killed yesterday by a sniper, is carried to his burial by his comrades.
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Nov. 23, 2012 - Aleppo, Syria - The brother of the Free Syrian Army fighter killed yesterday cries during his burial.
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Dec. 1, 2012 - Aleppo, Syria - A framed picture of Bashar al-Assad and his father Hafez is seen inside a toilet in a Free Syrian Army base.
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Nov. 28, 2012 - Aleppo, Syria - A Free Syrian Army fighter throws a grenade towards Syrian army soldiers.
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Nov. 29, 2012 - Aleppo, Syria - Free Syrian Army fighters battle government troops in Al Amryia neighborhood.
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Nov. 29, 2012 - Aleppo, Syria - A Free Syrian Army fighter walks in the rubble of the Al Amryia neighborhood.
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Nov. 29, 2012 - Aleppo, Syria - A Free Syrian Army fighter takes aim in the Al Amryia neighborhood.
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Nov. 29, 2012 - Aleppo, Syria - Blood covers the ground after the previous days gun fight in Al Amryia neighborhood. Rebel fighters said a mortar was dropped there and killed two of their comrades.
© Pau Rigol/zReportage/ZUMA
Nov. 20, 2012 - Aleppo, Syria - Fighters man a truck with a machine gun on the street in Aleppo's Tariq al-Bab neighborhood.
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Nov. 29, 2012 - Aleppo, Syria - A destroyed building lies in ruin where a bomb was dropped causing more than 15 civilian deaths in the Al Ansari neighborhood, according to locals.
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Nov. 29, 2012 - Aleppo, Syria - A Free Syrian Army fighter shoots at a government helicopter flying nearby.
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Nov. 29, 2012 - Aleppo, Syria - Smoke rises from damaged buildings after shelling.
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Dec. 3, 2012 - Aleppo, Syria - Free Syrian Army fighters get ready for battle against Bashar al-Assad's forces in Bustan Al-Pasha neighborhood.
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Nov. 18, 2012 - Aleppo, Syria - A portrait of a Free Syrian Army Fighter.
© Pau Rigol/zReportage/ZUMA