Five soldiers and two civilians have become fatalities in the Tripoli attack
Security sources in north Lebanon say two more people have died of their wounds from Monday's bomb explosion.
The deaths take the number of those killed in the incident to seven. It is not clear who carried out the attack, which targeted an army bus in Tripoli.
Earlier, the parliamentary majority leader denounced Syria's president for saying Tripoli and north Lebanon had become a base for extremists.
Saad Hariri said Syria posed a direct, clear threat to Lebanese sovereignty.
The fatalities on Tuesday were a civilian and a soldier, bringing the toll to five soldiers and two civilians.
Mr Hariri said Syria should not be allowed to intervene in Lebanese affairs under the pretence that it was opposing extremism in northern Syria.
Syria has said a bomb attack in Damascus on Saturday that killed 17 people was carried out by an Islamist militant from a neighbouring Arab country which it has not identified.
On Sunday Syrian President Bashar al-Assad reportedly told the head of the visiting head of Lebanon's journalists union that Sunni extremism in north Lebanon posed a threat to his country.
"The Lebanese will not let Bashar al-Assad's words go unnoticed," Mr Hariri said.
"His words are a clear and direct threat to the sovereignty of Lebanon and the north in particular," Mr Hariri said.