Syrian rebels have swept through parts of the country at lightning pace, taking control of the the second-largest city, Aleppo. But who are they and what are their aims?

The Syrian government has been fighting back against opposition forces with airstrikes after they took over large swathes of land in a lighting advance which has caused embarrassment to President Bashar Al-Assad.

Assad, the Syrian dictator, to retake Aleppo after part of the city fell to insurgents in 2012. Less than four days is how long it took him to lose it. On November 27th rebels launched a surprise offensive in north-west Syria.