BEIRUT, Lebanon — A blast from a powerful car bomb tore through a southern suburb of Beirut on Thursday, killing at least 18 people and wounding nearly 300 in the heart of a stronghold of Hezbollah, the militant Shiite movement that has the country's strongest military force.
The evening blast, which set apartment buildings ablaze and scattered bodies in the street, was the deadliest bombing in Lebanon in more than eight years and raised fears that the country was slipping into a new era of political violence.
Lebanon's prime minister, Najib Mikati, declared Friday a national day of mourning.
There were no credible claims of responsibility, but many here saw the bombing — and a similar attack nearby last month — as spillover from the civil war in neighboring Syria. Hezbollah has become increasingly involved there, sending fighters to back President Bashar Assad against the predominately Sunni rebels seeking his overthrow. That involvement has enraged Sunnis in both countries, and many said they suspected that extremists among them had used the blasts to strike back.
The explosion, near a complex often used for Hezbollah rallies in the Ruwais neighborhood, tore a hole in the street between two tall apartment buildings, blew the fronts off shops and burned a dozen cars, flipping some on top of others. Witnesses reported seeing bodies in the street afterward.
The attack was the deadliest in Lebanon since a car bombing in February 2005 killed the country's prime minister, Rafik Hariri, and 22 others.