A twin suicide bombing hit the southern suburbs of Beirut during the morning rush hour, killing at least seven people and wounding more than 100 in an attack targeting Iran's cultural centre, the country's health ministry said.
The blasts were caused by two suicide bombers of the Abdullah Azzam Brigades, an al-Qaeda-linked group that claimed responsibility for Wednesday's attacks via Twitter.
"In a little while, God willing, there will be important announcements on the attack of the Iranian cultural centre in Beirut by your brothers in the Abdullah Azzam Brigades, from the Hussein Bin Ali cell," it said.
We haven't left our homes for more than a month and a half. Every car I pass on the street is a potential car bomb. Unfortunately, I don't know if we have a future in Lebanon.
"We will continue... to target Iran and its party in Lebanon, in its security and political and military centres, until our demands are achieved," the group said.
"First: that the Party of Iran withdraws its forces from Syria. Second, that our prisoners are released from Lebanese prisons."
Among the dead were four civilians and one military officer, in addition to the two suicide bombers, the health ministry reported.
Al Jazeera's Basma Atassi, reporting from the scene of the explosions, said gunfire rang out from the area shortly after the blasts.
"There is widespread destruction in the area. People are crying and there is shooting going on now," Atassi said.
Television footage showed fire trucks and soldiers securing the area as ambulances raced to the scene.
A number of cars were badly damaged by the blasts. One was flipped onto its roof. Another was still ablaze several minutes after the blasts.
A wounded man was seen carried away on a stretcher and a young girl was being evacuated by two men. Glass covered the road and the facades of nearby buildings were torn off.
Lebanese television crews at the scene broadcast footage of widespread destruction, with emergency teams carrying wounded people away from a charred street strewn with rubble.
Numerous Lebanese politicians also live in the area, which is not far from Beirut airport.
The targeted area was metres away from the Kuwaiti embassy and a few hundred metres from the Iranian embassy, which was hit by a bomb attack in November that killed 23 people and wounded dozens.
Wave of bombings
A wave of bombings linked to the war in neighbouring Syria has struck Lebanon during the past few months, killing and wounding scores of people. Many have hit Shia areas of the capital.
Iran is a major backer of Hezbollah, a Lebanese Shia armed group and political movement. Both Iran and Hezbollah are allies with Syrian President Bashar al-Assad.
Syrian rebels have vowed to strike against Hezbollah in Lebanon in retaliation for its participation in the war.
Hezbollah blamed Saudi Arabia, a Sunni power that backs the Syrian opposition, for the November attack on the Iranian embassy.
The Lebanese security forces last week arrested a man identified as the al-Qaeda-linked mastermind of the recent string of car bomb attacks.
The arrest of Naim Abbas was followed by a security sweep that resulted in the seizure of a number of cars rigged with explosives and ready to be deployed.
Three years of civil war in Syria has spilled over into Lebanon, exacerbating Sunni-Shia tensions and triggering violence including frequent clashes between armed groups in the northern city of Tripoli.
The war has also affected Lebanese politics, leading to paralysis in government. Prime Minister Tammam Salam on Saturday finally managed to form a government grouping rival parties after the country went 11 months without a cabinet.