About two dozen people have reportedly been killed by Israeli airstrikes on southern Lebanon, less than 24 hours after a new ceasefire between Israel and Hezbollah was announced.

Local officials said 16 people had been killed in the Nabatieh district and seven in neighbouring Saida, with others injured, after Israeli warplanes, drones, and artillery targeted several areas.

A family of four - a father, a mother and their two children - was killed in the town of Barish in southern Lebanon, state media reported.

The Israeli military said it had struck "dozens" of Hezbollah targets after the group fired over 50 projectiles at Israeli forces in the region.

The US government has criticised Israel's ongoing operations in Lebanon, which was drawn into the US-Iran war when Hezbollah launched rockets into Israel in retaliation for a strike that killed Iran's supreme leader.

Washington also fears that the continuing tensions between Israel and Lebanon could undermine the US peace deal with Iran, which includes a commitment to end fighting on "all fronts" including Lebanon.

US envoy, Steve Witkoff, is reported to be heading to Switzerland for initial talks with Iran to help cement the agreement.

While it may have helped prevent a wider regional escalation for the time being, the deal leaves unresolved the central disputes at the heart of the conflict, including Israel's military presence in southern Lebanon and the future of Hezbollah's weapons.

A Hezbollah official told the BBC it does not recognise the ceasefire that was announced by US officials on Friday afternoon, and it rejects the Israeli objective to operate freely inside Lebanon.

Senior Hezbollah official Hassan Fadlallah said his group had the right to respond to Israeli attacks.

"What concerns us is that the enemy fully and comprehensively respects the ceasefire, and doesn't attempt to attack our country and villages or seek to occupy any new position," he said, as quoted in Lebanon's state-run National News Agency (NNA).

The Israel Defense Forces (IDF) said it had "struck dozens of Hezbollah terrorist infrastructure sites and terrorists in southern Lebanon".

The IDF said its strikes were in response to Hezbollah launching "more than 50 projectiles toward IDF soldiers in southern Lebanon".

"These attacks constitute repeated and ongoing violations of the ceasefire agreement," it added in the statement.

Previous ceasefires between Israel and Hezbollah have still seen near-daily cross-border strikes, with both sides accusing each other of violating the agreement.

Before Friday's ceasefire was announced, Israel said it had no intention of withdrawing its forces from Lebanon and had insisted that its conflict with Hezbollah was separate from the war on Iran.

Earlier on Friday, Lebanon's health ministry said 47 people were killed and 97 wounded in Israeli air strikes, while the Israeli military said four of its soldiers were also killed.

Ali, a Red Cross first responder in Nabatieh, told the BBC that it was "the most intense night" he can remember.

Those strikes came a day after the US and Iranian presidents signed an initial peace deal aiming to end the war, including in Lebanon, with immediate effect, but strikes continued.

The consequences of the ongoing fighting are visible across southern Lebanon.

At hospitals in the south, exhausted doctors continue treating the wounded, while emergency workers increasingly find themselves on recovery missions rather than rescue operations.

At Najdi Hospital in Nabatieh, ambulances bypass the emergency room and head straight to the morgue. Ali says there is no more room inside, and through the doorway, bodies in white bags can be seen laid out on the floor.

Many residents had returned to their villages after previous ceasefires and temporary truces, believing the worst of the fighting was behind them.

"The problem is that we got used to it," Ali says. "I have been with the Red Cross for more than 30 years, and deaths now are only a number for us."

The two countries first agreed to a ceasefire in April, but this failed to stop the fighting. Prime Minister Benjamin Netanyahu ordered his country's military to intensify its strikes on Hezbollah and advance deeper into Lebanon, after Hezbollah struck communities in northern Israel with drone and rocket attacks.

Ceasefire commitments have been repeatedly renewed since then, but followed by air strikes and attacks from both sides.

Netanyahu has been under domestic pressure to continue military action against Hezbollah, an Iran-backed Shia Muslim political and military group in Lebanon.

Hezbollah has vowed to continue its attacks while Israel's occupation of southern Lebanon persists.

Earlier this week, the White House criticised the Israeli government's military operation in Lebanon, saying it risks scuppering the peace deal. But speaking on Friday as he unveiled a new Air Force One jet, President Donald Trump praised Netanyahu, calling him a "warrior".

Lebanon was drawn into this conflict in early March, when Hezbollah launched rockets and drones into Israel. In response, Israel launched a bombing campaign across Lebanon. It is occupying around 5% of the country's territory in the south, with the aim of driving back Hezbollah fighters from its northern border.

Around a million people remain displaced, while dozens of communities in the south have been completely destroyed. (BBC)

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