Syria's Aleppo city bombed by fighter planes
July 25 , 2012
Fighter jets bombed parts of Syria's second city Aleppo on Tuesday.
The attack appeared to be in retaliation to an artillery barrage and comes after rebels launched an offensive against the city over the weekend in a bid to overthrow government forces.
The military's response marks a sharp escalation in the conflict.
U.S. Secretary of State Hillary Clinton has warned over the accelerating pace of events in Syria and has called on the opposition to be prepared for a transition of power.
She added it was not yet too late for President Bashar al-Assad to prepare for a handover.