British nationals have been urged to leave Syria immediately due to the ongoing civil unrest as troops backed by tanks mass at a town near the Turkish border. The Foreign and Commonwealth Office (FCO) said Britons should use commercial flights to leave while they are still available as it would be "highly unlikely" that its embassy in Damascus would be able to help if the situation were to deteriorate further. Evacuation options would also "be limited", it added. Violence between protesters opposed to Syria's leadership and the security forces has flared across the country, particularly near the border with Turkey, where thousands of refugees have fled. In the latest assault, Syrian troops backed by tanks and firing heavy machine guns swept into the village of Bdama, about 12 miles from the border, as the army intensified operations in the north-west of the country, which has seen the fiercest clashes.