A Syrian woman carries a ration of bread on her head in the northern city of Aleppo. The Syrian opposition now runs local councils in many cities, particularly in the north. They often face major challenges in providing basics likes food, water and electricity. Odd Anderson/AFP/Getty Images hide caption

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The Syrian military fired Scud missiles on rebel positions in northern Syria this week, a Pentagon source says. Here, a rebel fighter takes a position last month in the northern city of Aleppo, the scene of heavy fighting in recent months. Anonymous/AP hide caption

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To date, Syrian rebels have had to rely on small-scale weapons in their fight against the Syrian army. Here, a rebel fighter throws an explosive device toward a Syrian government position in the northern city of Aleppo last month. John Cantlie/AFP/Getty Images hide caption

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Rebel fighters take part in a demonstration against the Syrian regime after Friday prayers in Aleppo on Friday. Odd Andersen /AFP/Getty Images hide caption

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Syrian rebels say they now consider the Damascus International Airport to be part of the battle zone in their fight against Syria's government. Here, a U.N. vehicle is unloaded at the airport on May 12. Louai Beshara/AFP/Getty Images hide caption

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A Syrian soldier aims his rifle during clashes with rebel forces in the Damascus suburb of Daraya on Sunday. Syrian soldiers have been taking over private homes and apartments, and have sometimes looted and trashed them, according to Syrian civilians. HOPD/AP/SANA hide caption

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