A Hezbollah lawmaker said Tuesday that the Lebanese militant group would respond "double" to any Israeli attacks on civilians after a strike that killed three children and their grandmother in south Lebanon.

The remarks reflect the volatile situation on the Israeli-Lebanese border, where deadly clashes between Israeli troops and Iran-backed Hezbollah fighters are fueling fears of a wider regional war while Israel invades the Gaza Strip.

"The resistance will respond double to any aggression that targets civilians," Ali Fayyad said at the funeral of the four Lebanese killed in the south on Sunday.

"It hasn't yet shown all its weight," he said, referring to the powerful Iran-backed group. He did not elaborate.

Lebanese authorities said an Israeli strike hit the car the family was traveling in on Sunday. Israel's military said its troops engaged a vehicle in Lebanon which was "identified as a suspected transport for terrorists" and it was looking into reports there were civilians inside.

At the funeral, the family cried over four coffins draped in the flags of Lebanon and of a local scouts organization. A banner of the three girls, who were aged between 10 and 14, said they were martyrs and featured the emblem of Hezbollah.

Violence at the Lebanese-Israeli frontier is the deadliest there since 2006 as Israel bombards Hezbollah's Palestinian ally Hamas in Gaza — a response to an Oct. 7 Hamas attack on Israeli towns.

Hamas killed 1,400 Israelis, according to Israeli figures. Israel's bombardment of Gaza has killed 10,000 Palestinians, health officials in the enclave say.

Israel said on Monday it struck Hezbollah targets in response to a large barrage of rockets fired at northern Israeli cities.

The violence along the Lebanese border has killed more than 60 Hezbollah fighters and 10 civilians, Lebanese security officials say. At least seven Israeli soldiers and one civilian have been killed.