The al-Qaeda-affiliated Islamic State of Iraq and the Levant on Saturday claimed credit for a deadly bombing in the Beirut stronghold of the "criminal" Shiite militant group Hezbollah.
ISIL said in a statement posted online that it had penetrated the "security system of the Party of Satan (Hezbollah)... and crush its strongholds... in a first small payment from the heavy account that is awaiting those wicked criminals".
Thursday's suicide car bomb in the Haret Hreik district of the Lebanese capital killed four people and wounded 77.
It was the latest strike against the powerful party, whose fighters are aiding Syrian President Bashar al-Assad in a civil war that pits him largely against Sunni Muslims, including ISIL.
The army said on Saturday that a young man from northern Lebanon was the bomber who blew himself up.
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"The DNA test results on the remains of a suicide attacker found in the car used in the bomb attack... confirm they belong to the youth Qutaiba al-Satem," said the army.
"Investigations are ongoing by the relevant judicial authorities to uncover the full details of the event," it added.
An official from Satem's native Sunni-majority area of Wadi Khaled told AFP on Friday suspicions over the 20-year-old's role were based on a family document found at the scene of the blast.
Satem's father was then called in for DNA tests.
