BEKAA VALLEY, Lebanon — Since it erupted in March 2011, the Syrian war has seen heavy involvement by Lebanese Hezbollah, which has increased its presence there since 2013 to prop up the regime of President Bashar al-Assad.
Military sources close to Hezbollah estimate that the militant group may have deployed 7,000 to 9,000 fighters in Syria, specifically in areas around Damascus. The civil conflict has caused a large number of casualties among its ranks, with around 1,300 fighters killed in the last five years, according to the news website Ya Libnan.