Around 10 people were killed, including two children, and five were wounded in an Israeli strike on a residential building in the city of Nabatieh in south Lebanon, state news agency NNA said on Saturday.
The victims were all Syrian citizens, NNA said, adding that a final toll of the strike would be announced after DNA tests were conducted to determine the identity of the victims.
The Israeli military said the airstrike targeted a weapons depot used by Hezbollah.
Tensions have soared in the region in recent weeks, after a deadly rocket strike in the Israeli-occupied Golan Heights that Israel blamed on Hezbollah. Israel responded with the killing of a top Hezbollah commander in the suburbs of Beirut.
Hezbollah has also vowed to retaliate against Israel, as has Iran, for the killing in Tehran of Hamas political chief Ismail Haniyeh.