Syrian troops supported by Hezbollah operatives launched an offensive to retake a major town near Lebanon from rebels on Sunday, the heaviest fighting yet involving Lebanese armed group, opposition activists said.
At least 32 people were killed when rebel fighters clashed with mechanized Syrian army units and Hezbollah guerrillas in nine points in and around the town of Qusair, 10 km (six miles) from the border with Lebanon's Bekaa valley, they said.
Sources said that high-ranking Hezbollah officer Fady al-Jazzar was among those killed, pan-Arab news outlet Al Arabiya. According to the report, al-Jazzar was imprisoned in Israel until he was returned to Lebanon in a prisoner deal with Israel.
Speaking from Qusair, activist Hadi Abdallah said Syrian warplanes bombed Qusair in the morning and shells were hitting the town at a rate of up to 50 a minute.
"The army is hitting Qusair with tanks and artillery form the north and east while Hezbollah is firing mortar rounds and multiple rocket launchers from the south and west," he said.
"Most of the dead are civilians killed by the shelling."
The region near the Orontos River has been segregated into Sunni and Shi'ite villages in the civil war that grew out of protests against Syrian President Bashar Assad.
It is vital for Assad, who belongs to the Alawite sect, an offshoot of Shi'ite Islam, to keep open a route from Shi'ite Hezbollah's strongholds in the Bekaa to areas near Syria's Mediterranean coast inhabited by co-religionist Alawites.
Opposition sources say Syria's coastal region could serve as an Alawite statelet in case Assad falls in Damascus, in a potential fragmentation of Syria along ethnic and sectarian lines that raises the prospect of many more deaths.
Sources in Lebanon's Bekaa Valley said shells fired by rebels hit the edges of the town of Hermel, a stronghold of Hezbollah, which is backed by Iran, but no casualties were reported.
Syrian Television said the army is "leading an operation against terrorists in Qusair", with troops reaching the town's center.
"Our heroic forces are advancing toward Qusair and are chasing the remnants of the terrorists and have hoisted the Syrian flag on the municipality building. In the next few hours we will give you joyous news," the television said.