Why is there a war in Syria?

Even before the conflict began, many Syrians were complaining about high unemployment, corruption and a lack of political freedom under President Bashar al-Assad, who succeeded his late father Hafez in 2000.

In March 2011, pro-democracy demonstrations erupted in the southern city of Deraa, inspired by the "Arab Spring" in neighbouring countries.

When the government used deadly force to crush the dissent, protests demanding the president's resignation erupted nationwide.

The unrest spread and the crackdown intensified. Opposition supporters took up arms, first to defend themselves and later to rid their areas of security forces. Mr Assad vowed to crush what he called "foreign-backed terrorism".

The violence rapidly escalated and the country descended into civil war.