Tens of thousands of civilians are fleeing intense fighting in the embattled rebel-held districts of Aleppo , as the forces of President Bashar al-Assad make advances into the Syrian opposition’s last major urban stronghold and look set to split the opposition areas in two. On Monday the rebels appeared to have lost about a third of their territory in Aleppo city, according to estimates by the UK-based Syrian Observatory for Human Rights. Civilians fled several districts in the north-east as government forces advanced into some of the first areas to fall to rebel control in the summer of 2012. The rebel-held eastern neighbourhoods of Aleppo, Syria’s second city, have been under a fierce two-week Russian-backed air campaign, with aircraft pounding the area night and day. About 250,000 people have been trapped with little food or medical supplies during the months-long siege. Many fled as the front lines opened escape […]