Israel carried out airstrikes in southern Lebanon, killing at least six people, including three paramedics working at a health centre, just hours after its envoys had agreed with the Lebanese government to extend a ceasefire.

Israel also said it had killed the Hamas military chief, Izz al-Din al-Haddad, in a targeted strike in Gaza on Friday.

In a further sign that the region could be on the brink of a possible return to full-scale war, reports in the US and Israeli press said Donald Trump had been briefed on his military options in Iran, should he decide to break a five-week-old truce and resume strikes in the hope of forcing concessions at the negotiating table.

Lebanon’s state-run media reported that at least five villages in the south of the country had been hit by strikes, and the Israeli military confirmed on Saturday that it was targeting what it said was “Hezbollah infrastructure” in southern Lebanon.

Lebanese authorities said that an airstrike on Friday had hit a clinic run by the Hezbollah-linked Islamic Health Committee, killing six people, three of them paramedics. An Israeli military statement said it had killed Hezbollah militants preparing to fire rockets at its troops in southern Lebanon.

The new strikes, which triggered a fresh exodus of civilians from the south, came hours after envoys from Israel and Lebanon completed a round of talks in Washington, with an agreement to extend a month-long partly observed ceasefire for a further 45 days, and to establish a US-supervised security mechanism between their armies.

Hezbollah, however, has denounced the talks, while Israel has only partly observed the ceasefire ordered by Trump on 17 April, restricting attacks on Beirut and northern Lebanon in general while focusing its military operations in the south, where its troops have clashed with Hezbollah fighters.

Israel has also kept up operations in Gaza against Hamas, confirming on Saturday that it had killed Haddad, the latest acting Hamas military chief to die in Gaza, and the last surviving Hamas senior official suspected of planning the attack on southern Israel in October 2023, which killed 1,200 people and ignited the latest Gaza war.

Israel has accused Hamas of violating the fragile eight-month-old ceasefire in Gaza by refusing to disarm. For its part, Hamas has blamed Israel for failing to abide by the first phase of the truce, continuing airstrikes and stealthily moving the agreed demarcation line between the two forces westwards into Hamas-controlled parts of Gaza.

In recent days, the Israeli media has been predicting a return to full-scale war across the region, as truces fray amid scant diplomatic progress. As Trump returned to the US from a visit to China on Friday, the New York Times reported that he had been briefed on US options for returning to the offensive in Iran, but that he had yet to make a decision.

Pakistani-led mediation has failed to bring diplomatic progress in more than a month since Islamabad brokered a ceasefire in the Iran war, with the negotiating positions of the US and Iran still far apart.