Four people have been killed after two suicide bombers targeted the Iranian cultural centre in Beirut, Lebanon.

The attack was claimed by Sunni militants who said it was a response to the intervention of Iran and Hezbollah in the Syrian war.

The army said two cars packed with explosives had been used in the rush-hour attack in the predominantly Shia southern suburbs of Beirut.

Similar tactics were used in a twin suicide attack on the nearby Iranian embassy in November.

The attack, which wounded more than 100 people, was condemned by Lebanon's Sunni Prime Minister Tammam Salam as an act of terrorism.

The Abdullah Azzam Brigades, an al-Qaeda-linked group, claimed responsibility for the attack.

In a post on Twitter, the Brigades described the "twin martyrdom operation" on the Iranian centre as retaliation for Hezbollah's role in Syria and pledged more attacks.

The blast went off about 20 metres from the targeted building.

An official investigating the attack said a total of 160kg of explosives had been used.

The Iranian ambassador in Lebanon said the dead included a Lebanese policeman who had been guarding the cultural centre, but said none of its staff were wounded.

Iran's foreign ministry condemned the attack.

"There is no doubt that perpetrators of this terrorist act are the enemies of stability, security and unity of Lebanon," ministry spokeswoman Marzieh Afkham said in a statement carried by the official IRNA news agency.