( CNN ) -- Assassinations of high-profile government figures are not new to Lebanon . Some result from gruesome car bombs , ripping through people and buildings along bustling streets in cities like Beirut . For years , when such blasts occurred , Brig . Gen. Wissam al-Hassan led the investigations . He was credited with overhauling his nation 's intelligence forces , finding those responsible for targeted killings and preventing fresh attacks . No more . Al-Hassan and at least two others died in a massive explosion Friday in the typically peaceful and cosmopolitan Ashrafiyeh district of East Beirut that he called home . Lebanon on edge after anti-Syrian intel official killed by Beirut car bomb . The attack -- in broad daylight , at one of the capital 's busiest intersections -- was just the kind of thing the intelligence official worked so diligently to prevent . But beyond its potential impact on Lebanon 's security , al-Hassan 's life and death illustrates the deep political and religious fissures within Lebanese society -- fissures that could be widened amid spillover from Syria 's bloody civil war . `` The person who was the master of uncovering these kind of things ... is gone , '' said Amal Mudallali , a senior scholar at the Woodrow Wilson Center who , like al-Hassan , is affiliated with Lebanon 's `` March 14 '' movement . `` So unfortunately , the Lebanese are bracing for more assassinations . '' Al-Hassan was more than just Lebanon 's top intelligence official . He was an icon among many fellow Sunni Muslims , including those aligned with the opposition led by Saad Hariri , for his leadership and efforts in rooting out those responsible for targeted killings in Lebanon . But as much as he was loved by some , others despised him -- especially those backing Syrian President Bashar al-Assad and those affiliated with Hezbollah , the Shiite militant and political movement that has a prominent role in Lebanon 's government . The U.S. government labels it a terrorist organization . `` This is a very polarizing figure , '' said Aram Nerguizian , a fellow at the Center for Strategic and International Studies think tank who teaches in Beirut . In his position with Lebanon 's Internal Security Forces , al-Hassan tackled one of the nation 's bloodiest and politically volatile attacks , which occurred on February 14 , 2005 , in Beirut 's fashionable seaside Corniche district . On that day , an explosive-laden truck detonated as the motorcade of former Prime Minister Rafik Hariri -- Saad Hariri 's father -- passed by , killing the dignitary and 22 others . As Hariri 's chief of protocol , al-Hassan himself might have been among the dead had he not taken that day off to take a university exam . Details from al-Hassan 's investigation were shared with U.N. investigators , who concluded the assassination may have been linked to high-ranking Syrian officials ( despite denials from Damascus ) . A U.N. tribunal went on to indict four Hezbollah members , and left the door open for more to be charged , though that group 's leader , Hassan Nasrallah , blamed Israel for Hariri 's death . Al-Hassan spearheaded several other investigations into a series of killings that targeted major anti-Syrian political figures . And he is credited with uncovering an Israeli spy network that involved Lebanese agents , including a top aide to Hezbollah 's powerful Christian ally , Michel Aoun . His latest big break , occurring in late August , came with the arrest of a former Lebanese minister and current member of parliament , Michel Samaha . Lebanese security forces claim a recording shows Samaha -- who has close ties with Damascus and is now in jail awaiting trial -- attempting to smuggle in explosives intended to be used in religious and political assassinations . Two Syrian security officers also were charged . `` Unfortunately , today , al-Hassan paid the price for his success , '' Saad Hariri said . Twice in the years after Rafik Hariri 's death , al-Hassan had skirted death . The second assassination attempt left one of his top aides , Wissam Eid , dead . With his absence , others within Lebanon 's security apparatus will step into his place . Photos : Aftermath of the Beirut blast . But describing Friday as `` a grim day , '' Mudallali said finding someone who can do the same thing as al-Hassan -- whom she lauds for his `` great achievements '' in unraveling complex cases -- will be difficult . `` I do n't think Wissam al-Hassan -- somebody with his experience , with his background -- is going to be replaced very easily , '' she said .
Brig . Gen. Wissam al-Hassan was a top intelligence official in Lebanon . Aligned with an anti-Syrian , anti-Hezbollah faction , he led many probes into assassinations . Fellow Sunnis saw him as an icon , while he was despised by others . A scholar linked to the opposition calls al-Hassan a `` master '' who will be difficult to replace .