Lebanon's Iran-backed Hezbollah movement said Thursday that five of its fighters, including the son of a senior lawmaker, had been killed, amid skirmishes at the Israel-Lebanon border since the Israel-Hamas war began.

Abbas Raad, son of the head of Hezbollah's parliamentary bloc Mohammed Raad, was "martyred on the road to Jerusalem", the group said in a statement -- the phrase it has been using to announce the death of its members due to Israeli fire since the war started on October 7.

It issued separate statements with the identities and photographs of four other fighters who were also killed.

A source close to the family, requesting anonymity as they were not authorised to speak to the media, told AFP that Abbas Raad "was killed with a number of other Hezbollah members" in an Israeli strike Wednesday on a house in south Lebanon's Beit Yahun.

Lebanon's official National News Agency said Wednesday that "an air strike launched by the Israeli enemy... on a house in Beit Yahun killed four people". It did not identify the victims.

Since the Israel-Hamas war began on October 7, the frontier between Lebanon and Israel has seen escalating exchanges of fire, mainly between Israel and Shiite Muslim movement Hezbollah, but also Palestinian groups, raising fears of a broader conflagration.

Israel's army said in statements Wednesday evening that it had struck a number of Hezbollah targets and sources of fire from Lebanon, including a Hezbollah "terrorist cell" and infrastructure.

Since the cross-border exchanges began, 107 people have been killed on the Lebanese side, according to an AFP tally. At least 75 are Hezbollah fighters but the toll also included at least 14 civilians, three of them journalists.

Seven Hezbollah fighters have also been killed in Syria.

On the Israeli side, six soldiers and three civilians have been killed, according to authorities.

The strike came just hours after a four-day truce in Gaza was announced between Israel and Hamas, a Hezbollah ally.

Iran's Foreign Minister Hossein Amir-Abdollahian, who visited Beirut on Wednesday, warned in an interview that if the Hamas-Israel ceasefire begins but "does not continue... the conditions in the region will not remain the same as before the ceasefire and the scope of the war will expand".