Syrian military forces have captured areas near the border with Lebanon, cutting supply lines for foreign-backed insurgents as the army tightens its grip northwest of the capital, state media say. Syrian troops are approaching the mountain resort of Zabadani, which has been under rebel control for two years, cutting it off from insurgent-held areas in the mountainous Qalamoun region, state TV said on Friday. Syrian forces have systematically captured most of the insurgent-held towns along the mountainous frontier since launching an offensive in the region in November. State TV said troops in the Qalamoun region reached the edge of the Lebanese border town Tufeil. The Britain-based Syrian Observatory for Human Rights reported clashes in the area on Friday. A Syrian army officer told state TV that the aim of the operation is to cut crossing points the armed militants use for supplies and "to separate Qalamoun from Zabadani." "With this operation, our heroes of the Syrian Arab Army have tightened their grip on armed groups and they will all be killed in the areas that they fled to," said the officer, whose name was not given. The foreign-sponsored insurgency in Syria, now in its fourth year, has reportedly killed almost 160,000 people. Nearly three million Syrians have fled the country.