Saturday's attack on the Omran cafe in the neighborhood of Jabal Mohsen left nine people dead and wounded more than 30.
The Lebanese Army confirmed that two Lebanese attackers strapped with 4-kilo suicide vests were behind the attack.
A statement identified the two attackers as Taha Samir al-Khayal, 22, and Bilal Mohammad al-Mariyan, 29.
The Nusra Front had claimed responsibility for the twin blasts in Jabal Mohsen, a majority Alawite neighborhood which had witnessed years of deadly, Syria-related clashes with rival neighborhood Bab al-Tabbaneh.
Saturday’s explosion is the first serious breach to a security plan implemented in June 2014 that ended years of clashes between the neighborhoods.
"A suicide operation targeted a cafe [belonging to] the Alawite Arab Democratic Party," the Nusra Front said on its social media pages, in reference to Jabal Mohsen's dominant group the ADP.
According to security sources both of the attackers are Lebanese and received their training in the mountainous region of Syria's Qalamoun on the border with Lebanon. The attackers were said to be supporters of wanted Tripoli terror suspects Shadi Mawlawi and his partner Osama Mansour.
The two are wanted over attacks on military posts in Tripoli.
Khayal is from the Roummanah neighborhood of the city and Mariyan is from the Mankoubeen neighborhood had not been seen since October, after supporters of Mawlawi and Mansour withdrew from the Abdallah bin Masoud Mosque in Bab al-Tabbaneh following deadly clashes with the Army.
The attackers were thought to have fled to Syria along with other gunmen affiliated to Mawlawi and Mansour.
The families said they were shocked to find out there sons were fighting in the Qalamoun when they were thought to have fled to Syria months ago.
The father of Khayal handed himself over to Army Intelligence late-Saturday after the attack.
All of Tripoli witnessed high Army presence Sunday as the military dispatched patrols and erected checkpoints across the city.
Soldiers mostly concentrated around the Jabal Mohsen neighborhood as well as the Mankoubeen neighborhood - the area of residence of one of the suicide bombers.
Forensic experts are also investigating the scene of the attack and collecting evidence.
The area surrounding the cafe, which was cordoned off last night, was reopened Sunday morning, but the Army is keen on limiting the number of individuals gathering on the streets in Jabal Mohsen and the Mankoubeen neighborhood.
According to a security source, soldiers have been ordered to disband any gathering of people due to fears of further attacks.
According to the source, residents are wary of another possible attack as the Army pursues armed supporters of Mawlawi and Mansour in the Mankoubeen neighborhood.
Security forces are asking about individuals from the Mankoubeen area who haven’t been spotted for a while and are thought to be in Syria. There are over a dozen young men who have been out of sight for months, and are thought to be planning further attacks in Lebanon, the sources said.
