Rebel forces in Syria have taken control of the "majority" of the country's second-largest city, Aleppo, observers said. The offensive is the largest against the Syrian government in years and the first time rebels fighting the forces of President Bashar al-Assad have reached Aleppo since being forced out by the army in 2016. It is thought that more than 300 people - including more than 20 civilians - have been killed since the offensive started on Wednesday. Overnight, Russia has launched air strikes at rebel targets in the city, and a Kremlin spokesman expressed his support for "the government of Syria to quickly restore order”. Subscribe here: http://bit.ly/1rbfUog For more news, analysis and features visit: www.bbc.com/news #Syria #BBCNews