Unknown persons have fired three missiles from Lebanon towards Israel, according to the Israeli army.
Two of them landed in Israel and one hit the ground in Lebanon, the army said in a statement on Wednesday, adding that it had responded with artillery fire towards Lebanon.
There were initially no reports of casualties in Israel.
According to a Lebanese security source, six Israeli shells later landed in Lebanon. There were initially no reports of injuries or damage.
The Israeli army also said there was a missile alert in several locations in the north of the country. Residents were told to go to the shelters, media reported.
According to the report, a fire broke out after the impact of a missile.
Israeli media said the army assumed that Palestinian groups had fired the missiles, but an army spokesperson did not initially want to confirm this.
Just two weeks ago, two rockets were fired from Lebanon towards northern Israel. One was intercepted by the Iron Dome defence system, while the other fell in an open area inside Israel. In response, Israel struck targets in Lebanon.
Israeli army officials said at the time that Palestinian factions in Lebanon might be responsible.
A Lebanese security source, speaking on condition of anonymity, also said a hardline Palestinian group might be behind the launching of the rockets.
At the beginning of July, Israeli Defence Minister Benny Gantz offered humanitarian aid to the neighbouring crisis-hit country.
At the same time, Lebanese caretaker Prime Minister Hassan Diab issued an urgent call for help from the global community to save the country as it struggled with a severe economic crisis.
Israel and Lebanon are officially at war, and there are recurring tensions along the border between the Israeli army and the Lebanese Iran-backed Hezbollah movement