"There is no doubt that perpetrators of this terrorist act are the enemies of stability, security and unity of Leb," ministry spokeswoman Marzieh Afkham said in a statement carried by the official IRNA news agency.
"(They) are agents of the Zionist (Israeli) regime who have been frustrated by the formation of a new government that includes all parties and tribes in Leb," she added.
At least four people were killed in Wednesday's bombings that also maimed at least 100 others.
IRNA earlier reported that the blast took place near its office in Beirut, as well as that of the state broadcaster IRIB.
The Beirut attack -- linked to the conflict in neighboring Syria whose regime is fiercely supported by Tehran -- was quickly claimed by the Abdullah Azzam Brigades
... Leb's current al-Qaeda affiliate, named after a guy whose car the current head of al-Qaeda had boomed...
, a jihadist group inspired by al-Qaeda.
The group had previously claimed an attack against Iran's embassy in Beirut, located in a southern stronghold of the Tehran-backed Hizbullah.
...
Party of God, a Leb militia inspired, founded, funded and directed by Iran. Hizbullah refers to itself as
The Resistanceand purports to defend Leb against Israel, with whom it has started and lost one war to date, though it did claim victory...
Hizbullah is fighting alongside Syrian
Hereditary President-for-Life Bashir Pencilneckal-Assad
The Scourge of Hama...
's troops against Sunni-led rebels.