Israeli warplanes have attacked what the army called a Palestinian militant base south of the Lebanese capital Beirut.
An army spokeswoman said the raid was in response to missile attacks on Israel.
Israel claimed the target was being used as a training base for the Popular Front for the Liberation of Palestine.
It is not yet known if there were any casualties.
The attack came just a few hours after three rockets were fired on the town of Kiryat Shmona in northern Israel, from the direction of southern Lebanon.
Israeli army sources blamed Lebanon’s Hizbollah group but there was no confirmation from the militants.
There has been an intensification of attacks on both sides in recent days.Israel has promised that any act of aggression by Palestinian militants will be met with retaliation.