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Tens of thousands flee Syria's largest city

July 30, 2012 12:00:00 AM PDT
The U.N. said 200,000 Syrians have left Aleppo over the past 10 days as the government trains its mortars, tanks and helicopter gunships on the neighborhoods seized by the rebels.

Greece is sending 1,800 more guards to its border with Turkey because of the potential influx of refugees from war-torn Syria.

Unrest continued Monday in Syria as regime forces attacked rebel positions. Fighting continues in Aleppo, Syria's commercial capital and largest city. Control of Aleppo is crucial to both sides.

The Free Syrian Army is desperately trying to hold on to neighborhoods they had recently taken. Regime forces have responded with tanks and helicopter gunships.

The Associated Press contributed to this report.