Hezbollah launched hundreds of rockets and drones against Israel on Sunday in retaliation for the assassination of a senior commander in Beirut last month, the
, as Israel's cabinet met to prepare a response.
The Israeli military said it had thwarted a much larger attack with pre-emptive strikes after it assessed that Hezbollah was preparing to launch the barrage.
Sunday's violence was among the biggest exchanges of fire since hostilities began between Israel and Hezbollah in parallel with the eruption of Israel's war against
.
Around 100 Israeli jets struck more than 40 Hezbollah launch sites in southern Lebanon shortly before the strikes, destroying thousands of launcher barrels that were aimed mainly at northern Israel but with some targets in central areas, the Israeli military said in a statement.
Hezbollah said it had launched drones and more than 320 Katyusha rockets towards Israel and hit 11 military targets.
It said the barrage had completed "the first phase" of its response to
but that the full response would take "some time".
It dismissed Israel's account of the pre-emptive strikes but said in a statement its military operation had been completed successfully for the day.
Expectations of an escalation between the two sides had risen since
and the Israeli military assassinated Shukr in Beirut in response.
Israel's cabinet met at 7am (2pm AEST), Prime Minister Benjamin Netanyahu's office announced, but there were no immediate details on any further response from Israel.
"We are determined to do everything possible to defend our country, to return the residents of the north safely to their homes and to continue to uphold a simple rule: Whoever harms us — we harm him," Netanyahu said in a statement.
Foreign Minister Israel Katz said Israel would respond to developments on the ground but did not seek a full-scale war.
Most of the Israeli strikes were hitting targets in southern Lebanon but the military was ready to strike anywhere there was a threat, an Israeli military spokesperson said.
Israeli defence minister Yoav Gallant declared a 48-hour state of emergency, and flights to and from Ben Gurion airport in Tel Aviv were suspended for around 90 minutes, but the airport's authority said normal operations were expected to resume by 7am.
Jordan's flag carrier Royal Jordanian suspended flights to Beirut on Sunday "due to the current situation", the state news agency reported without giving an exact time frame for the suspension.
Fears of a wider conflict
The Israel-Hezbollah escalation
, potentially involving both the United States and Iran. President Joe Biden was following events closely, the White House said.
"At his direction, senior US officials have been communicating continuously with their Israeli counterparts. We will keep supporting Israel’s right to defend itself, and we will keep working for regional stability," said National Security Council spokesperson Sean Savett.
The strikes came as negotiators were meeting in Cairo in a last-ditch
and a return of Israeli and foreign hostages in exchange for Palestinian prisoners.
Hezbollah fired missiles at Israel immediately after the October 7 attacks by Hamas gunmen on Israel.
Hezbollah and Israel have been exchanging fire constantly ever since, while avoiding a major escalation as war rages in Gaza to the south.
That precarious balance appeared to shift after the strike in the Golan Heights, for which Hezbollah denied responsibility, and the subsequent assassination of Shukr, one of Hezbollah's most senior military commanders.
Shukr's death in an airstrike was quickly followed by
, which led to vows of reprisal against Israel by Iran.
The past 24 hours
In northern Israel, warning sirens sounded and multiple explosions were heard around several areas as Israel's Iron Dome aerial defence system shot down rockets coming from southern Lebanon. Israel's Magen David Adom ambulance service said it was on high alert all over the country.
The Israeli military issued civil defence instructions from central Israel to the north, limiting gatherings but authorising people to go to work as long as they were able to reach air raid shelters quickly. There were no casualties immediately reported in Israel, according to the ambulance service.
A security source in Lebanon said at least 40 Israeli strikes had hit various towns in the country's south in one of the densest bombardments since hostilities began in October.
One of the strikes on the town of Khiam killed one fighter from the Hezbollah-allied Shi'ite group Amal, two security sources told Reuters. Amal later announced his death.
A resident of the southern Lebanese town of Zibqeen, some 7 km (4 miles) from the border, told Reuters it was the first time he had awakened "to the sound of planes and the loud explosions of rockets — even before the dawn prayer. It felt like the apocalypse."
Israel's Army Radio, citing defence officials, said the military assessed that the Hezbollah barrage on northern Israel was "improvised" after the pre-emptive strike by Israeli jets on the Hezbollah launch sites.
In a message addressed to the residents of southern Lebanon early Sunday morning, the Israeli military said: "We are monitoring Hezbollah's preparations to carry out large-scale attacks on Israeli territory near your homes. You are in danger. We are attacking and eliminating Hezbollah threats.
"Anyone who is near areas where Hezbollah operates should leave immediately to protect themselves and their families," the message posted on Telegram said.
Hezbollah said it had "began an air attack with a large number of drones" targeting Israeli territory, the statement said, while fighters had also targeted "a number of enemy positions and barracks and Iron Dome platforms ... with a large number of rockets".
The "military operations will take some time to complete", it said.
