The Lebanese military added that a soldier had been killed in a separate Israeli strike "while he was driving on the road" in the Nabatieh region.

The strikes come as Lebanon and Israel prepare for a fourth round of US-brokered talks early next month.

A ceasefire between Israel and the Iran-backed Lebanese group Hezbollah was supposed to have taken effect on April 17 but has never been observed.

Both sides accuse each other of violating it and justify their attacks by the other camp's alleged breaches of the truce.

Lebanon was dragged into the wider Middle East war in early March when Hezbollah launched rocket attacks on Israel in retaliation for the US-Israeli attacks on Iran, prompting Israeli strikes and a ground invasion.

The Israeli military on Wednesday declared all areas south of Lebanon's Zahrani River, an area roughly 40 kilometres (25 miles) from the border, "combat zones" and told residents to evacuate ahead of attacks against Hezbollah.

Lebanon's health ministry said in a statement that an airstrike on a building in the city of Sidon on Thursday killed five people, including two women, and wounded 21, five of them children.

An AFP correspondent reported that the raid destroyed the first two floors of a residential building, with rescuers evacuating the dead and wounded, including at least one body.

In another statement, the health ministry said "the Israeli enemy's raid at dawn today targeting a vehicle in the town of Adloun, Sidon district, resulted in six martyrs, including two children, their mother and their father".

The state-run National News Agency (NNA) said strikes targeted several other areas in the south.

Lebanon's civil defence agency, meanwhile, told AFP there had been eight strikes on the southern city of Tyre since Wednesday evening, in addition to others on its outskirts, after Israel issued evacuation warnings to residents.

The NNA said several buildings, a cafe and a motorcycle were among the targets.

An AFP photographer saw fire and a thick plume of smoke rising at dawn and heard bombardment, after a strike on a building in Tyre.

Ghazouane Halawani, a resident living near a building hit by a strike, told AFP that he believed Israel wanted to attack the ancient city's "history and its civilisation".

"We're staying here. This is our country, our land, our life," he added.