A rebel mortar attack on a school outside Damascus on Tuesday killed 29 people, Syria's state news agency SANA said. According to the report, 28 students and one teacher were killed at the school in Wafideen Camp, in the Damascus suburbs.
Over the border in neighboring Lebanon, two men were killed and 12 wounded in sectarian clashes in the port city of Tripoli between gunmen loyal to opposing sides in neighbouring Syria's civil war, residents said.
The army cut off all roads leading to the area on Tuesday evening as militants launched rocket-propelled grenades at each other along Syria Street, a main thoroughfare that has become synonymous with fighting over the past year.
Tensions had been building since the deaths of at least 14 Lebanese and Palestinian gunmen from north Lebanon in a Syrian town close to the border. They appeared to have joined insurgents waging a 20-month-old revolt against Syrian President Bashar Assad.
Syrian state television has shown graphic footage of the dead men, riddled with gunshot wounds and lying in the grass. Lebanon's Foreign Minister Adnan Mansour asked the Syrian ambassador to hand over the bodies of the men after their families protested in Tripoli to demand the Lebanese government return the dead and determine the whereabouts of the missing.
Tripoli's sectarian divisions have made it a flashpoint within Lebanon where violence from Syria has sometimes spilled over. The Syrian uprising is mostly being waged by Sunni Muslims and largely opposed by minorities like Assad's own Alawite sect.
Tripoli is a majority Sunni city and mostly supports the uprising next door, but the coastal city has an Alawite minority and clashes have erupted several times since the revolt began. Residents said violence flared overnight when rocket-propelled grenades were fired by gunmen in the Sunni neighbourhood of Bab al-Tabbaneh and the Alawite area of Jabal
Fighting then broke out on Tuesday morning after Sunni gunmen approached some Alawite shops.
Earlier this week on Sunday, Syrian army forces pounded rebel-held suburbs around Damascus with fighter jets and rockets, activists said, killing at least 10 and wounding dozens in an offensive to stop rebels closing in on the capital.
In Syria's central city of Homs, a car bomb killed at least 15 people and wounded 24 on Sunday, Syria's state news agency SANA said. It said the blast in the city's Hamra district also damaged many nearby residential buildings.
Rebels planned to push into the Damascus city center from their strongholds on the outskirts and fighting has been fierce. The army sent reinforcements after a week of rebel advances, including the capture of two military bases near the capital.
Also on Sunday, Lebanon's state news agency reported Lebanese soldiers have exchanged fire across the border with rebels in neighboring Syria.
The state-run National News Agency said late Sunday that Lebanese soldiers stationed near the village of Qaa in the Bekaa Valley returned fire into Syria after "armed men" shot at them from across the frontier.
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