Tel Aviv confirmed the strikes in southwest Lebanon on Wednesday, but the Islamist resistance movement declined to comment.
However, Lebanon's al-Manar Television said Hizb Allah had opened fire on Israeli warplanes, as did the Lebanese army.
Locals say about a dozen Israeli jets swooped over swathes of the country, but no planes were reported hit.
Lebanese security sources said Israeli jets struck hillsides, from where witnesses saw two plumes of black smoke rising, near the southern port city of Tyre. It is unclear if anyone was hurt.
The United Nations, which has repeatedly warned that overflights and anti-aircraft fire could lead to a more serious conflict, expressed "great dismay" at Wednesday's escalation.
"One violation cannot justify another," the UN envoy for southern Lebanon said in a statement, urging "Israel to halt its overflights and the Lebanese side to halt the ensuing and dangerous anti-aircraft fire".
Israel has flown regular sorties over Lebanon since withdrawing its troops from most of the country in 2000 after a 22-year occupation.