Senior Lebanese intelligence official Wissam al-Hassan is among at least eight people killed in a car bomb attack in Beirut, according to state media. More than 78 others were wounded.
The explosion happened in Sassine Square, a busy area in the predominantly Christian district of Ashrafiya in the city’s centre.
Witnesses say the huge blast could be heard several kilometres away. A multi-storey building was badly damaged, while several cars in the street were destroyed.
The intended target of the attack is unclear, but it occured at a time of heightened tensions between Lebanese groups as a result of the conflict in Syria.
The bomb exploded on the street which houses the headquarters of the Maronite Christian group, Kataeb, who are also known as the Phalange.
Phalange leader Sami al-Gemayel, a staunch opponent of Syrian President Bashar al-Assad, condemned the attack.
“Let the state protect the citizens. We will not accept any procrastination in this matter, we cannot continue like that. We have been warning for a year. Enough.”
Ambulances rushed to the scene of the blast, while security forces have surrounded the area.
Hospitals are now appealing for blood donations to help dozens of people with serious injuries.
The last bombing in Beirut was in 2008 when three people were killed in an explosion which damaged a US diplomatic car.
Tension between Sunnis and Shi’ites has been rumbling in Lebanon ever since the end of the 1975-1990 civil war but reignited after the Syria conflict erupted.
It reached its peak when former prime minister Rafik al-Hariri, a Sunni, was killed in 2005.
Hezbollah’s political opponents, who have for months accused it of aiding Assad’s forces, have warned that its involvement in Syria could stoke sectarian tensions.