One of the suicide bombers responsible for Tuesday's deadly attack on the Iranian embassy in Lebanon is a follower of a firebrand Sunni preacher, a judge said, after the man was identified through DNA tests on his father.

Mouin Abu Daher was initially suspected after his father, Adnan Abu Daher, told authorities that he believed his son was one of the bombers, the judge told the Associated press news agency, speaking on condition of anonymity because he was not allowed to release the information.

A Facebook page reportedly belonging to Mouin Abu Daher expressed support for al-Qaeda and for Sunni Muslim Lebanese cleric Sheik Ahmad al-Assir, who is a supporter of the Syrian rebellion.

The suspect's link to al-Assir, known for his sermons denouncing Iran's Lebanese Shia ally Hezbollah, which has backed Syrian forces battling rebels, is likely to increase already rising tensions between the country's two largest Muslim groups.

Tuesday's double suicide bombing, which killed 23 people, targeted the Iranian embassy in an upscale Shia-dominated neighbourhood of Beirut, the Lebanese capital.

An al-Qaeda-linked group, the Lebanese Abdullah Azzam Brigades, claimed responsibility for the attack, one of the deadliest in a series of attacks targeting neighbourhoods perceived to be sympathetic to Hezbollah in recent months.

They said it was payback for the military support that Iran and Hezbollah provide to the Syrian government of Bashar al-sssad against the mainly Sunni rebels fighting to overthrow his rule.

The victims included a 54-year-old Iranian diplomat, Ibrahim Ansari, who oversaw regional cultural activities.

The Syrian conflict, in its third year, also has become a confrontation between regional powers, chiefly Iran and Saudi Arabia. It has also created tensions in Lebanon over Hezbollah's open participation in the conflict to shore up Assad forces.

Source: Agencies