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The red lines crossed by Israel in assassinating Hezbollah commander Fouad Shukr and Hamas leader Ismail Haniyeh will usher in a “new phase” of the multifront conflict that will make Israel “weep", Hezbollah leader Hassan Nasrallah said on Thursday.
"You don’t know what red lines you have crossed,” Mr Nasrallah said in a speech broadcast after Mr Shukr's funeral in Beirut.
"The enemy must await the rage and revenge of the honourable people of this nation."
Mr Shukr and an Iranian military associate were killed in an Israeli strike on a densely populated neighbourhood in Beirut's southern suburb of Dahieh on Tuesday night. Three women and two children also died, and dozens were injured.
Hours later, Hamas leader Ismail Haniyeh was killed in an explosion at his residence in Tehran after attending the inauguration of Iran's new President Masoud Pezeshkian.
Israel acknowledged carrying out the drone strike that killed Mr Shukr but not the attack that killed Mr Haniyeh. The means by which the Hamas leader was killed has yet to be established, with some reports suggesting it was a missile strike and others that it was a bomb planted at his residence and detonated remotely.
Mr Nasrallah said the assassination of Mr Haniyeh was an assault on Iran’s “sovereignty, national security, prestige – and especially on their honour".
“The Israelis and people of the West do not know what honour means in the East," he said. "To Iran, the martyr-leader Haniyeh was a guest in [their] home, and you [Israel] have killed their guest.”
The assassinations intensified western calls for de-escalation.
"They want us to mitigate our retaliation," Mr Nasrallah said. "They try to minimise the aggression that took place on us: the people of southern Beirut and on the resistance."
Thousands of people waving Hezbollah, Palestinian and Iranian flags gathered in Dahieh for Mr Shukr's funeral.
A young man who declined to give his name said he had expected Mr Nasrallah to say what he did.
"We knew there would be a response, we knew that targeting Dahieh and children was a red line," he said.
As for the nature and timing of the retaliation, he said Mr Nasrallah always took "measured decisions". He added that "even if this starts a war, we will be ready".
Jana, a young woman in the crowd, told The National: "The killing of our commanders doesn't make us weaker, on the contrary, it makes us stronger."
She said she was not afraid of a war. "We will stay here in our land, even if Israel destroys everything."
The Lebanese capital had been on tenterhooks for days, awaiting Israeli retaliation for a rocket attack on the town of Majdal Shams in the Israeli-occupied Golan Heights that killed a dozen children. Israel and the US blamed the attack on Hezbollah, which denied any involvement.
Israel said Mr Shukr orchestrated the attack, but Mr Nasrallah again denied Hezbollah was involved, instead accusing Israel of firing an interceptor missile that landed in the town.
"If we bomb a village we have the courage to take responsibility, even if it was a mistake. We would have admitted to it, just as we have done in the past," he said.
"The enemy's accusations against us are intentional and aim to cause strife."
The UK’s Foreign Secretary David Lammy and Defence Secretary John Healey arrived in Beirut on Thursday in a bid to calm tensions. They met caretaker Prime Minister Najib Mikati, parliament speaker Nabih Berri and caretaker Foreign Minister Abdallah Bou Habib.
"Israel has violated Lebanese sovereignty, assaulted our land in violation of international laws, and assaults civilians in a blatant manner daily," Mr Mikati told the delegation.
He said the solution to the crisis was implementing international resolutions, including UNSC Resolution 1701, which brought an end to the month-long war Israel and Hezbollah fought in 2006.
That resolution has never been fully implemented.
The two ministers visited Qatar on Wednesday, which has been a key mediator between Hamas and Israel.
Mr Lammy told the British parliament on Tuesday that the risk of a full-scale conflict was rising. He urged British citizens to leave Lebanon.
It came as Israel’s ambulance service concluded a massive three-day drill on Wednesday simulating a mass casualty event in the event of a war in the north of the country, as tensions spiral with Hezbollah
The drill included scenarios simulating electricity and communications being lost, mass casualties after rocket strikes and urgent blood donations. They also involved the use of satellite technology, specialist vehicles and call centres that are able to operate in the event of severe logistical challenges.
Israel’s military has been conducting drills in the north ever since hostilities began with Hezbollah on October 8, but ones by health authorities are rarer.
The Magen David Adom ambulance service’s simulation came in the aftermath of a rocket strike in the occupied Golan Heights that killed 12 children on a football field.
Crushing blows
As Hezbollah confirmed the death of the top military commander, Israeli Prime Minister Benjamin Netanyahu said on Wednesday night his army has dealt “crushing blows” against Hamas, Hezbollah and Yemen's Houthis in recent days, as he praised the Israeli strike that killed Mr Shukr.
He described the commander as the “deputy” of Mr Nasrallah and accused him of being in charge of the attack on Majdal Shams as well as numerous other attacks on Israel.
However, he did not directly mention the assassination of Hamas leader Ismail Haniyeh. Israel is widely suspected of carrying out the attack but has not officially claimed it.
The nearly 10-month conflict between Israel and Hezbollah is widely thought to be on the brink of a surge in violence which experts warn could cause devastation in both countries, particularly Lebanon, which has been in the grip of a sustained economic crisis.
The regional escalation began on October 7 with a surprise Hamas attack on southern Israel, killing about 1,200 people, mostly civilians. Israel’s retaliation has devastated Gaza, killing more than 39,400 people, also mostly civilians.
Israel-Hezbollah violence has already killed more than 500 people in Lebanon, about 100 civilians and the rest fighters. Nearly 50 civilians and soldiers have been killed on the Israeli side.
An Israeli strike killed four people – a Syrian woman and her three children – in the southern town of Shaams on Thursday, Lebanon's Ministry of Health said. It was the first Israeli attack on the town since the near-daily cross-border attacks with warplanes, drones, rockets and artillery began.
Israel and Hezbollah last fought a major conflict in 2006, a 34-day war that devastated parts of Beirut, killing about 1,200 people in Lebanon, mostly civilians, and about 160 in Israel, mostly soldiers.
Analysts say both sides are now vastly more equipped in terms of firepower, with Hezbollah thought to possess up to 150,000 rockets and missiles, 10 times its arsenal in 2006. Israel has expanded its air force, in part shown by devastating attacks on Gaza, leaving most of the enclave with a population of 2.3 million in ruins.
