'Twin suicide attack' in Beirut kills four
At least four people have been killed and dozens wounded in a twin bomb attack in the south of the Lebanese capital Beirut, officials say.
Security sources said it appeared that two suicide bombers using a car and a motorcycle had blown themselves up near an Iranian cultural centre.
The blasts caused heavy damage to shops and buildings and set fire to vehicles.
It is the latest in a series of attacks in Beirut's southern suburbs, where Hezbollah has a strong presence.
Radical Sunni militant groups have said they will continue to target the Shia Islamist movement's strongholds until it pulls its forces out of Syria, where they are fighting on the government's side.
Iran provides significant financial and military support to both Hezbollah and President Bashar al-Assad. It denies having sent combat troops to Syria, saying they are serving only as advisers.
Hezbollah's TV station, al-Manar, reported that in Wednesday's attack, the first bomber detonated a car laden with explosives near the Iranian cultural centre in the Bir Hassan district. Almost simultaneously, the second assailant set off a bomb hidden in his motorcycle, it added.
Officials told the Associated Press that security forces in the area had suspected one of the men was about to attack and opened fire on him, apparently forcing both to detonate their bombs prematurely.
The explosions sent a large plume of smoke into the sky. Fire engines and ambulances headed to the area and were seen evacuating the wounded.
The Iranian embassy said that there were no serious casualties among its staff at the cultural centre. Blast walls were reportedly recently installed in front of the facility.
The bombs also exploded near the Kuwaiti embassy, a Lebanese army barracks, the Beirut offices of the Iranian state news agency Irna and state broadcaster Irib, and an orphanage run by an Islamic charity.
The orphanage's windows were blown out and children were seen peering out of them, crying and screaming "bomb, bomb", according to the Reuters news agency. Several were among the injured.
Prime Minister Tammam Salam, who on Saturday managed to form a coalition government including rival parties after 11 months of trying, said the attack was "a message by forces of terrorism to continue in their plan to spread death in Lebanon".
"We got the message and we will respond to it with solidarity and our commitment to peace," he added.
A Twitter account associated with the al-Qaeda-linked Abdullah Azzam Brigades said there would soon 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".
In November, the jihadist group claimed a similar double suicide bomb attack on the Iranian embassy, which killed more than 20 people.
Since then, there have been more explosions, despite extreme security measures taken by the Lebanese authorities and by Hezbollah itself, reports the BBC's Jim Muir in Beirut.
Last week, security forces arrested a man they identified as the mastermind of the bomb attacks. Naim Abbas was detained after a number of cars rigged with explosives were discovered.