Rebels surrounded a government-held Druze village on the Syrian side of the ceasefire line on the Golan Heights today after heavy fighting, a monitoring group said.
The advance came a day after Israel, with a significant Druze minority, said it was preparing for the possibility that people fleeing fighting might seek to cross to the Israeli-occupied side of the strategic plateau.
Prime Minister Benjamin Netanyahu said Israel was "closely following what is happening close to our borders," and that he had "given instructions to do what is necessary."
He did not elaborate.
After fierce clashes with loyalists, rebels, including Islamist fighters, surrounded the village of Hader, the Syrian Observatory for Human Rights monitor said.
"Hader is now totally surrounded by rebels, who just took a strategic hilltop north of the village," Observatory director Rami Abdel Rahman told AFP.
The village lies along the ceasefire line, with the Israeli-occupied Golan to the west and the border with Damascus province to the northeast.
Abdel Rahman said the rebels had received reinforcements from elsewhere in Quneitra province, which covers much of the Golan.
"The regime has not sent reinforcements yet, but the Druze villagers are standing with the government," he added.
Fighting around Hader, which began yesterday, has killed at least 10 rebels and 14 loyalists so far, he said.
The encirclement of Hader comes amid rising fears in Syria's Druze community.
Last week, 20 Druze villagers were killed in an altercation with members of Al-Qaeda's Syrian affiliate Al-Nusra Front in Idlib province in the northwest.
Shortly afterwards, rebels in southern Syria briefly overran a government air base in majority-Druze Sweida province, in their first such advance in the government-controlled region.
While the rebels were eventually expelled from the base, fighting has continued nearby.
The Druze are followers of a secretive offshoot of Shiite Islam, and made up around three per cent of Syria's pre-war population of 23 million.
