Aarsal in many ways illustrates the Syrian conflict's transformation from an uprising against an authoritarian regime into a sectarian civil war with reverberations around the region.
Lebanon's army said it lost 16 soldiers in a battle with gunmen loyal to Sheikh Ahmad al-Assir, a once-obscure Salafi cleric who has seen his profile rise by verbally attacking Hezbollah.
Hezbollah fighters are assisting Syria's government in taking on rebels across the country.
Lebanon, which lived under Syrian occupation for 30 years and has battled its own bloody sectarian wars, is now in the crosshairs of a spiraling regional conflict.
Hezbollah is stepping up its support of the Syrian government, helping it retake key rebel strongholds on the road to Damascus.
Sectarian violence in Lebanon may resemble Syria's conflict, but residents say the real problems are poverty and neglect.
Kidnapping for ransom is one of the few forms of economic activity to flourish here as the civil war in neighboring Syria cripples the tourism industry and erodes the authority of the state.
Sectarian tensions between Sunni and Shiite in Syria are threatening an uneasy peace in Lebanon.