A look at the front lines of Syria's civil war

(CBS News) The head of U.N. observers in Syria said Tuesday the uprising against Syria's dictator has grown into a full-scale civil war.

Rebel forces control parts of several cities, and Bashar al-Assad's army is using everything in its arsenal to get them back, including tanks and artillery.

Also on Tuesday, U.S. Secretary of State Hillary Clinton accused Russia of supplying attack helicopters to Assad's army.

Few western journalists have been able to get inside Syria, but CBS News correspondent Elizabeth Palmer was able to drive to the center of the conflict near the city of Homs.

Palmer reports she found miles and miles of devastation near the front lines of the war, as well as neighborhoods that thousands had fled from as the fighting worsened.

Above, watch Palmer's report from the front lines of Syria's civil war, including the story of a family walking across those lines to reach rebel-held territory, and of the increasing use of helicopter gunships by the Syrian army.

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