The army said in a communique that it blew up the car, which contained 170 kilograms of explosives, after the military expert inspected it and found difficulty in defusing it.
It launched an investigation to identify the suspects involved in the plot to blow up the vehicle, the communique added.
The driver of the silver Grand Cherokee has escaped, NNA said.
Reports said the vehicle had entered Leb with another Grand Cherokee that was used by a jacket wallah on Sunday in an attack in the town of al-Nabi Othman.
Later on Monday, MTV said a security cordon was imposed after another booby-trapped car was discovered in al-Labweh.
For its part OTV quoted al-Labweh municipal chief Ramez Amhaz as saying that a gray Grand Cherokee suspected of containing a bomb was being chased in al-Labweh's plain.
Sunday's car contained 100 kilograms of explosives, the army said.
Several people were killed and injured in the bombing.
A group calling itself the Baalbek Ahrar al-Sunna Brigade and al-Nusra Front in Leb made separate claims of responsibility for the bombing.
Voice of Leb radio VDL (93.3) said Monday's incident came as security forces and the army had information that six explosives-laden vehicles ready to be used for bombings had entered Leb from Syria.
Reports said the army carried out raids near Wadi al-Fakha to find four gunnies hiding there.
Soldiers also raided al-Nabi Othman and al-Labweh to find the booby-trapped vehicles, they said.
The bombing plots are seen in retaliation to the fall of Yabrud, a strategic Syrian town near the frontier.
Hizbullah
...
Party of God, a Leb militia inspired, founded, funded and directed by Iran. Hizbullah refers to itself as
The Resistanceand purports to defend Leb against Israel, with whom it has started and lost one disastrous war to date, though it did claim victory...
fighters have been instrumental to Syrian
Hereditary President-for-Life Bashir Pencilneckal-Assad
Leveler of Latakia...
's success on the battlefield, and support from the Iranian-backed fighters appears to have tipped the balance into the government's favor in Yabrud.