Syrian rebel forces claim they killed at least 40 Hezbollah and Iranian fighters in Damascus, according to Israel Radio.
The rebels say they detonated a car bomb near a compound where the operatives from Iran and Hezbollah gathered for a meeting, Israel Radio reported. These claims could not be independently corroborated.
Last month, the UN Security Council called on Lebanese Hezbollah militants to end any involvement in the conflict in neighboring Syria, while Lebanon's UN envoy pledged that his country would keep its borders open to Syrians fleeing the violence.
Hezbollah has sent thousands of fighters to help Syrian President Bashar Assad's forces combat rebels, according to Israeli and Western estimates. Israel is now boosting its forces on the Syrian border, where it believes Hezbollah is preparing for the day when it could fight Israel.
"The Security Council calls upon all Lebanese parties to recommit to Lebanon's policy of disassociation, to stand united behind President Michel Sleiman in this regard and to step back from any involvement in the Syrian crisis," the UN body said.
The statement did not explicitly name Hezbollah due to objections from Russia, council diplomats said. But they added that it was clear Hezbollah was the intended target of the council declaration.
The 15-member council also expressed grave concern at the influx of almost 600,000 refugees into Lebanon during the conflict, which started more than two years ago as mainly peaceful protests against Assad, but descended into a civil war.
The United Nations says as many as 100,000 people have been killed in Syria and four million have been internally displaced, while nearly two million have fled to neighboring countries.
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