The Lebanese army on Sunday accused Israel of sending a reconnaissance drone at the weekend over Beirut's southern suburbs, a bastion of the Shiite militant Hezbollah group.
On August 25, two explosives-laden drones were sent to the same area. One of them exploded, sparking a dangerous escalation between Hezbollah and Israel.
On Saturday night, "one of the Israel enemy's reconnaissance drones violated Lebanese air space... overflew the southern suburbs and left," the army said in a statement.
The Iran-backed Hezbollah is represented in Lebanon's government and parliament but is considered a terrorist organisation by Israel and Washington, which has stepped up the financial pressure on the organisation.
The August incident heightened regional tensions, which culminated in a cross-border exchange of fire in early September.
Hezbollah vowed then that it would shoot down any Israeli drones violating Lebanon's air space.