Lebanese Prime Minister Saad Hariri said two Israeli drones which crashed in a suburb of Beirut dominated by the Iranian-backed Hezbollah were designed to stir up regional tensions.
One drone fell and second exploded before dawn and caused some damage to Hezbollah's media centre in the southern Dahiyeh suburbs, a Hezbollah official told Reuters, in the first such incident since the two sides waged war in 2006.
"The new aggression…constitutes a threat to regional stability and an attempt to push the situation towards further tension," Hariri said in a statement from his office.
The Israeli military declined to comment.
A spokesman for Lebanon's Hezbollah group said that Israeli drones that fell in Beirut had certain "targets" which investigations had so far not established.
Hezbollah's media officer Muhammad Afif told reporters in televised comments that the group's "position in response to this aggression" would come in the speech of the group's leader Sayyed Hassan Nasrallah later on Sunday.
The incident took place hours after the Israeli military said its aircraft had struck Iranian forces and Shi'ite militias near Syria's capital Damascus which it said had been planning to launch "killer drones" into Israel.
War monitor the Syrian Observatory for Human Rights said two members of Hezbollah, one Iranian and two more people of an unknown identity were killed in the Israeli strikes.
Lieutenant-Colonel Jonathan Conricus, an Israeli military spokesman, told reporters "a number of attack drones", each armed with several kilogrammes of explosives, were to have been launched simultaneously at targets in northern Israel on Thursday but the plan was thwarted.
He did not disclose what measures Israel took that day. He described the "killer drones" – designed to slam into targets – as highly accurate. Conricus said the drones, accompanied by "Iranian operatives", had arrived at Damascus airport from Iran several weeks ago and were taken to a Quds-controlled compound in a village southeast of the city.
Israel carried out Saturday's attack, Conricus said, after learning that another attempt to launch drones was imminent.
