Tensions on the Israel-Lebanon border soared Wednesday amid growing violence and Tel Aviv's reported approval of a cross-border military operation.

The Israeli military said its warplanes had struck Hezbollah sites in southern Lebanon overnight and Wednesday morning.

Lebanon's official National News agency confirmed Israeli strikes on several areas in south Lebanon. They killed three Hezbollah members, the group said.

Lebanese media reported multiple Israeli strikes along the border and in an area north of the coastal city of Tyre, about 30 kilometers (20 miles) from the frontier.

The Israeli military said two Hezbollah launches damaged several vehicles in northern Israel.

Meanwhile, a U.S. envoy tasked with avoiding a devastating regional war returned to Israel after meeting officials in Lebanon.

Amos Hochstein, a senior adviser to U.S. President Joe Biden, was back in Israel after meetings in Lebanon on Tuesday.

There has been no word on whether he has made progress in his efforts to avoid a wider war.

'Approved and validated'

The latest clashes come a day after the Israeli military said that "operational plans for an offensive in Lebanon were approved and validated."

Israel's war on Gaza has heightened tensions across the region, with Israeli forces and Lebanon's Iran-backed Hezbollah, a Hamas ally, exchanging fire on a near-daily basis.

"Operational plans for an offensive in Lebanon were approved and validated" as commanders met for a situational assessment, the army said in a statement.

Separately, Israeli Foreign Minister Israel Katz has also threatened Hezbollah's destruction in a "total war."

U.S. envoy Amos Hochstein, who is in the region to de-escalate tensions, said the latest plan proposed by President Joe Biden would ultimately lead to "the end of the conflict in Gaza" which would in turn quell fighting between Israel and Hezbollah.

But Israel's top diplomat on Tuesday said: "We are very close to the moment when we will decide to change the rules of the game against Hezbollah and Lebanon."

"In a total war, Hezbollah will be destroyed and Lebanon will be hit hard," Katz said in a statement from his ministry.

It came after Hezbollah published a more than nine-minute video showing drone footage purportedly taken by the movement over northern Israel, including parts of the city and port of Haifa.