Israel said on Friday it would evacuate more than 20,000 residents from Kiryat Shmona, one of the biggest towns on its northern border with Lebanon following a heavy cross-border exchange of fire in the area the day before.
The Israel-Lebanon border has seen constant, but so far limited, clashes since a war in Gaza erupted two weeks ago.
Israel had already declared some areas along the frontier as closed military zones, forcing residents to move away, but this is the largest evacuation from the lush hills of the eastern Galilee region.
"We reaffirm that the killing of civilians and the assault on the security of our country will not go without response or punishment," Hezbollah said in a statement.
Daniel Hagari, spokesperson for the Israel Defense Forces (IDF), said: "This kind of evacuation, which has already been done in a number of towns on the northern border, allows the IDF to expand its operational freedom to act against the Hezbollah terrorist organisation."
Persistent violence along the Israel-Lebanon border has raised fears that fighting between Israel and Hamas Islamists in Gaza could spiral into a broader, regional conflict.
Israel's military said one of its drones "struck a terrorist in Lebanese territory" overnight. It also said it targeted Hezbollah assets in response to rockets fired from Lebanon.
Evacuees from Kiryat Shmona will be put up in state-subsidised guesthouses, Israel's Defense Ministry said, joining tens of thousands of Israelis who have already left their homes near the southern Gaza border.
The Committee to Protect Journalists has said it has documented more than 20 journalists killed since the start of the Israel-Gaza conflict and said it was investigating reports of other journalists killed, injured and reported missing.
The latest incident on the Israel-Lebanon border came nearly a week after Reuters journalist Issam Abdallah was killed in southern Lebanon. Lebanon's army blamed Israel and Israel's military says it is reviewing the case. Reuters has called on Israel to conduct a "thorough, swift and transparent investigation".
