Syrian rebels have driven government forces from Hama, a major city that the country’s regime had held over more than a decade of civil war, further weakening President Bashar al-Assad’s grip on the nation.

The Islamist rebels’ breakneck advance has redrawn the country’s front lines and revealed the fragility of the government’s security forces.

Syrian rebels captured the city of Hama on Thursday, a major victory in a week-old lightning advance across northern Syria and a devastating new blow to President Bashar al-Assad and his Russian and Iranian allies.