Local Syrian doctors prepare to treat a patient in a field hospital in Aldana, Syria, near the Turkish border. Each day, local and expatriate doctors take big risks to treat the wounded in rebel-held areas. Deborah Amos/NPR hide caption

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Syrian rebels pose after seizing control of the Bab al-Hawa border post on the Syrian-Turkey border on July 20. Now, the rebels are facing a new challenge: radical Islamists, who they say do not represent them. Bulent Kilic/AFP/Getty Images hide caption

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Rebel fighters take up position near the military airport outside the rebel-held town of Azaz in northern Syria on Aug. 21. In rebel-held towns like Azaz, activists are taking on new, risky roles as the uprising against Syrian President Bashar Assad continues. Youssef Boudlal/Reuters/Landov hide caption

itoggle caption Youssef Boudlal/Reuters/Landov

Syrian rebels captured the Bab al-Salam crossing on the border with Turkey in July. Large numbers of refugees fleeing northern Syria for Turkey come to the crossing, which is orderly and well-run, at least for now. Adem Altan/AFP/Getty Images hide caption

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Syrians gather by the rubble of a house destroyed by shelling in the northern town of Azaz, on the outskirts of Aleppo, on Monday. Muhammed Muheisen/AP hide caption

itoggle caption Muhammed Muheisen/AP

Syrians take refuge Thursday at the Bab Al-Salameh border crossing near the Syrian town of Azaz, in hopes of entering one of the refugee camps in Turkey. Muhammed Muheisen/AP hide caption

itoggle caption Muhammed Muheisen/AP

Syrian children, who fled their home with their family, take refuge at the Bab Al-Salameh border crossing, in hopes of entering one of the refugee camps in Turkey on Sunday. Muhammed Muheisen/AP hide caption

itoggle caption Muhammed Muheisen/AP

The daily fighting in Syria included this gun battle Wednesday involving rebels in the northern city of Aleppo. Still, the rival sides recently worked out a prisoner swap in which two women were freed from state custody, while the rebels released seven pro-government fighters. James Lawler Duggan/AFP/Getty Images hide caption

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Syrians fleeing increased violence arriving last week at the border between the Syrian town of Azaz and the neighboring Turkish town of Kilis. Phil Moore/AFP/Getty Images hide caption

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