Hundreds of Islamist gunmen fired in the air on Monday as they laid to rest a Sunni Muslim cleric whose killing ignited street battles that brought the bloodshed of Syria's uprising across the border into Lebanon.
Sheikh Ahmed Abdul Wahid, an opponent of Syrian President Bashar al-Assad, was shot dead a day earlier at a Lebanese army checkpoint in a part of Lebanon where Sunni sympathy is with Syria's rebels.
Demonstrators blocked roads and burned tyres in the northern province of Akkar, and similar protests in Beirut gave way to firefights with machineguns and rocket-propelled grenades.
The clashes on Monday between gunmen from the Future Movement, loyal to anti-Syrian former Prime Minister Saad al-Hariri, and members of a pro-Syrian party, left two dead and were the worst unrest in Beirut since sectarian fighting brought Lebanon to the brink of civil war in 2008.
Khaled Daher, a member of parliament from the Future Movement, said Abdul Wahid was the victim of an "intentional assassination" by Lebanese troops he said were loyal to Damascus, which demands Lebanon cut the flow of arms to the mainly Sunni rebels in Syria.
Syria flooded Lebanon with troops early in its 1975-1991 civil war and dominated its smaller neighbour for over a decade afterwards. It retains significant influence over Lebanon's intelligence apparatus and military.
Its 14-month-old uprising has rippled into Lebanon, where fighting between Sunni Muslim fighters, Assad supporters who belong to his minority Alawite sect, and Lebanese troops killed eight people in the northern city of Tripoli last week.
Mourners bore the bodies of Abdul Wahid and Muhammed Mraib, another man killed in the checkpoint incident, to a mosque in Albireh in Akkar, the coffin of the latter man shrouded in the standards of the rebel Free Syrian Army and the Future Movement.
Lebanon's prime minister, himself from Tripoli, has appealed for calm and vowed steps to preserve civil peace. Judicial sources said 20 soldiers were being questioned over the checkpoint killing, following demands for their prosecution.
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