BEIRUT—The assassination by car bomb on Friday of a prominent Lebanese political figure who was critical of the Shiite militia Hezbollah has raised the specter of greater instability in Lebanon, fueled by the war across the frontier in Syria.
There was no immediate claim of responsibility for the enormous blast in Beirut targeting Mohamad Chatah, a former Lebanese ambassador to the United States. But the Syrian conflict has already left a lasting mark on its politically fragile neighbor.
The explosion, which also killed at least five other people and injured more than 70, took place in a central commercial district close to downtown hotels and government buildings, including the parliament, and reverberated across Beirut, sending a plume of black smoke into the sky. Hours later, bloodstains marked the pavement as white-clad forensic experts examined the scene, which was littered with twisted metal, shattered glass and scorched debris.
Chatah, 62, was on his way to a meeting of a political faction opposed to the Syrian government when the bomb — thought to have contained more than 120 pounds of explosives — detonated as his convoy passed.
The deadly attack drew widespread condemnation. Caretaker Prime Minister
U.S. Secretary of State
"His presence will be missed, but his vision for a united Lebanon, free from sectarian violence and destabilizing interference, will continue to guide our efforts," Kerry said. "Indeed, his tragic end reminds all of us just why his vision remains so imperative."
Some associates of Chatah, including former Prime Minister
An economist and diplomat, Chatah was closely tied to the Future movement, which has called on Hezbollah to halt its paramilitary operations in Syria. He also was a member of a mainly Sunni Muslim group called the March 14 bloc, which is opposed to the Syrian government and had convened the meeting he was to attend.
Chatah was a confidant of successive Lebanese leaders, including former Prime Minister Rafik Hariri, who was assassinated in a similar manner in February 2005, when his motorcade was hit by a massive bomb not far from the scene of Friday's attack.
The assassination of Chatah comes less than three weeks before a special tribunal is to open proceedings against four members of Hezbollah who have been implicated in Hariri's killing. All reject the accusations, and none will be present; one is believed to be fighting in Syria.
Chatah's stance on the Syria conflict put him at sharp odds with Hezbollah. In what was apparently his final tweet, sent an hour before the blast, he wrote: "#Hezbollah is pressing hard to be granted similar powers in security & foreign policy matters that Syria exercised in Lebanon for 15 yrs."
Syria sent troops into Lebanon in 1976. Between 1991 and 2005, its military presence in Lebanon was legitimized with a treaty between the two countries, but Hariri's assassination sparked an uprising that came to be known as the Cedar Revolution, which forced Syria to withdraw.
Spillover violence from the Syrian civil war has led to a string of bombings and other attacks in Beirut, the Lebanese capital. But previous deadly strikes have mainly taken place in the city's Shiite-dominated southern neighborhoods, rather than in the commercial center, chic and bustling after being rebuilt following Lebanon's devastating civil war.
Last month, a pair of bombings outside the Iranian Embassy compound in Beirut killed 23 people and injured more than 150. Iran, a prime player in Syria's civil war, is a backer of Hezbollah and Syrian President Bashar Assad.