Lebanese President Michel Aoun said on Thursday Israel's overnight airstrikes, the first since 2006, showed an escalation in its "aggressive intent" towards his country.
Aoun also said in a tweet the strikes were a direct threat to the security and stability of southern Lebanon and violated UN Security Council resolutions.
Israeli jets struck what its military said were rocket launch sites in Lebanon early on Thursday in response to two rockets fired towards Israel from Lebanese territory.
The rockets launched from Lebanon on Wednesday struck open areas in northern Israel, causing brush fires along the hilly frontier. There was no claim of responsibility for the attack.
Israel responded with several rounds of artillery fire on Wednesday before launching airstrikes early on Thursday, the military said.
The border has been mostly quiet since Israel fought a 2006 war against Hezbollah, which has advanced rockets.