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. After years locked behind frozen frontlines, the rebels have burst forth to mount the swiftest battlefield advance by either side since a rebellion against Assad descended into civil war 13 years ago. The capture of Hama gives them control of a strategic central city they never managed to seize before. The Syrian army said it was redeploying outside the city “to preserve civilian lives and prevent urban combat” after what it called intense clashes. Rebels were seen on television parading through Hama into the evening to the sound of celebratory gunfire. They said they were ready to march on south towards Homs, a key crossroads city that links the capital Damascus to the north and to the coast. “Your time has come,” said a rebel operations room in an online post, calling on Homs residents to rise up in revolution.