BEIRUT -- Syrian troops clashed with rebels in a mountainous western region Saturday in what appeared to be an offensive to cut an opposition supply route from Lebanon, forcing hundreds to flee for safety across the border, activists and officials said.
The fighting was concentrated in the rugged Qalamoun region around the towns of Qara, Rima and Nabak, activists and state media said. The battle has been expected for weeks as troops and opposition fighters reinforced their positions ahead of winter, when much of the area is covered with snow.
The Britain-based Syrian Observatory for Human Rights said the fighting had closed the highway linking Damascus with the central city of Homs. It said Syrian warplanes struck rebel held areas around Qara and nearby mountains.
The Observatory added that Lebanon's militant Hezbollah group has deployed thousands of fighters on the Lebanese side of the border in preparation for the battle. Hezbollah's fighters openly joined Syria's civil war earlier this year, tipping the war in favor of government forces mostly in the central province of Homs and in the suburbs of Damascus.
Syria's state-run news agency said troops had killed "tens of terrorists" in attacks on rebel hideouts in areas including Nabak and Rima. The government refers to rebels fighting to overthrow President Bashar Assad as terrorists.
The Qalamoun region is a main rebel supply route for weapons and fighters from neighboring Lebanon. Government forces appear to be trying to regain control of the whole border with the country.