© Jalaa MareyAn Israeli policeman inspects the impact crater left by a rocket fired from southern Lebanon in the northern city of Safed
While the rocket fire was not immediately claimed, the exchanges raised fears of a broader conflict between Israel and the Iran-backed Hezbollah movement, which have been trading near daily cross-border fire since the Israel-Hamas war began in October.
The Israeli army said in a statement Sergeant Omer Sarah Benjo, 20, was killed "as a result of a (rocket) launch carried out from Lebanese territory on a base in northern Israel".
Fighter jets struck a series of "Hezbollah terror targets" in several areas of south Lebanon including Adshit and Sawwaneh, the military said.
Comment: Not really:
Lebanon's state-run National News Agency (NNA) said Israeli warplanes targeted a house in Sawwaneh with two strikes, "leading to its destruction" and the death of three members of the same family, identifying them as a Syrian woman and her child, aged two, and stepchild, 13.
The NNA said another Israeli attack targeting Adshit killed one person, who Hezbollah announced was one of its fighters, and wounded 10 others, destroying a building and causing significant damage nearby.
'Heavy price'
Israel's Magen David Adom emergency service had said seven people were wounded in fire from Lebanon, five of them in the town of Safed.
An AFP photographer saw medics and troops evacuating a wounded person by military helicopter from Safed's Ziv hospital.
Israeli army chief Herzi Halevi said after meeting commanders near the Lebanese border that Israel's "next campaign will be very much on the offensive, and we will use all the tools and all capabilities".
"We are intensifying the strikes all the time, and Hezbollah are paying an increasingly heavy price," he said in a statement.
Senior Hezbollah official Hashem Safieddine said Wednesday that "this aggression... will not go unanswered".
A day earlier, Hezbollah chief Hassan Nasrallah said that fire from southern Lebanon would end "when the attack on Gaza stops and there is a ceasefire" between the group's Palestinian allies Hamas and arch-foe Israel.
"If they (Israel) broaden the confrontation, we will do the same," Nasrallah warned.
Tens of thousands of people have been displaced on both sides of the border amid soaring regional tensions.
Fears have been growing of another full-blown conflict between Israel and Hezbollah, which last went to war in 2006.
'Diplomatic path'
The UN secretary-general's spokesman Stephane Dujarric warned "the recent escalation is dangerous indeed and should stop."
Peacekeepers from the United Nations mission in Lebanon had noticed "a concerning shift in the exchanges of fire between the Israeli armed forces and armed groups in Lebanon", he added.
The attacks included the "targeting of areas far from the Blue Line", he said, referring to the withdrawal line demarcated by the UN in 2000 after Israeli troops pulled out of southern Lebanon.
State Department spokesman Matthew Miller said Washington would continue to push for a "diplomatic path" to resolve the cross-border tensions.
"One of our primary objectives from the outset of this conflict is to see that it not be widened," he added.
US National Security Advisor Jake Sullivan said that "Hezbollah has been firing deeper and deeper into Israel," adding that the threat from the Iran-backed group had become "acute".
The cross-border violence has killed at least 248 people on the Lebanese side, most of them Hezbollah fighters but also including 33 civilians, according to an AFP tally.
On the Israeli side, 10 soldiers and six civilians have been killed, according to the Israeli army.
And they want the US to wage it for them.