A family of three, a father, his wife and their son were killed Tuesday in an Israeli strike on a house in the southern border village of Houla.
The National News Agency said the three killed were civilians but Hezbollah later announced the death of the father, Hassan Hussein, and his 25-year-old son, Ali Hussein, "on the road to Jerusalem" -- the phrase used for Hezbollah fighters killed by Israel.
Hussein, his wife, Ruwaida Mustafa, and their son were killed in a raid on a three-storey house in Houla, NNA said.
"Search operations and the removal of rubble are continuing," it added.
Shortly after the deadly strike, Hezbollah said it launched "dozens of rockets" at the Israeli kibbutz of Kfar Blum, six kilometers from the nearest border point.
The group also said it "targeted a building" in the Israeli city of Kiryat Shmona and another building in Avivim.
It said it acted "in response to the Israeli aggression against the villages of the south and the homes of civilians," among them the strike on the house in Houla.
Hezbollah also said it carried out several attacks on Israeli military positions on the border on Tuesday.
On Monday, a missile fired from Lebanon killed a foreign worker in Israel, according to the army, and three Hezbollah-affiliated paramedics were killed in an Israeli raid on southern Lebanon, according to the group.
NNA had also reported on Monday evening that Israeli air raids targeted the border town of Bint Jbeil, but no casualties were reported.
It came as U.S. envoy Amos Hochstein said a diplomatic solution was key to ending nearly five months of intensifying hostilities between Hezbollah and Israel.
"A diplomatic solution is the only way to end the current hostilities" and achieve "a lasting fair security arrangement between Lebanon and Israel", he said, adding "a temporary ceasefire is not enough".