Israel’s claim to have killed Nasrallah came after sources close to Hezbollah had told Reuters that he was alive. Iran’s Tasnim news agency also reported he was safe.

The Israeli military had already claimed to have killed Muhammad Ali Ismail, the commander of Hezbollah’s missile unit, and his deputy Hossein Ahmed Ismail.

At the United Nations, Israeli Prime Minister Benjamin Netanyahu vowed to “continue degrading Hezbollah” until Israel achieved its goals. His comments dampened hopes for a US and Australia-backed call for a 21-day truce to allow time for a diplomatic solution. Hezbollah has not responded to the proposal.

“As long as Hezbollah chooses the path of war, Israel has no choice, and Israel has every right to remove this threat and return our citizens to their homes safely,” he said.

Several delegations walked out as Netanyahu approached the lectern.

News of the blasts came as Netanyahu was briefing reporters after his UN address. A military aide whispered into his ear, and Netanyahu quickly ended the briefing to return to Israel.

The attack on the group’s headquarters levelled multiple high-rise apartment buildings, killing at least six people and wounding 91, Lebanon’s Health Ministry said. The death toll was likely to rise significantly as teams combed through the rubble of six buildings.

Iranian Foreign Minister Abbas Araghchi said Iran would be “on the side of Lebanon and resistance by all means” and accused the US of complicity.

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“Just this morning, the Israeli regime used several 5000-pound bunker busters that had been gifted to them by the United States to hit residential areas in Beirut,” he told a UN Security Council meeting on the Middle East.

US Defence Secretary Lloyd Austin said he did not have any advance warning of the strikes.

US President Joe Biden has directed the Pentagon to “assess and adjust as necessary US force posture” in the Middle East, the White House said. “He has also directed his team to ensure that US embassies in the region take all protective measures as appropriate.”

Israeli army spokesman Rear Admiral Daniel Hagari said the strikes targeted the main Hezbollah headquarters, saying it was located underground beneath residential buildings.

The series of blasts at around nightfall reduced six apartment towers to rubble in Haret Hreik, a densely populated, predominantly Shiite district of Beirut’s Dahiyeh suburbs, according to Lebanon’s national news agency. A wall of billowing black and orange smoke rose into the sky as windows were rattled and houses shaken some 30 kilometres north of Beirut.

Footage showed rescue workers clambering over large slabs of concrete, surrounded by high piles of twisted metal and wreckage. Several craters were visible, one with a car toppled into it. A stream of residents carrying their belongings was seen fleeing along a main road out of the district.

Israel provided no immediate comment about the type of bomb or how many it used, but the resulting explosion levelled an area greater than a city block. The Israeli army has in its arsenal 900-kilogram American-made “Bunker Buster” guided bombs designed specifically for hitting subterranean targets.

Richard Weir, crisis and weapons researcher with Human Rights Watch, said the blasts were consistent with that class of bomb.

To a degree unseen in past conflicts, Israel this past week has aimed to eliminate Hezbollah’s senior leadership. Confirmation of the assassination of Nasrallah would be a major escalation.

Nasrallah has been in hiding for years, very rarely appearing in public. The site hit on Friday evening (Beirut time) had not been publicly known as Hezbollah’s main headquarters, though it is located in the group’s “security quarters”, a heavily guarded part of Haret Hreik where it has offices and runs several nearby hospitals.

The Israeli army later warned residents to evacuate three buildings in other southern Beirut neighbourhoods, saying it was about to strike them because Hezbollah was using them to hide weapons.

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Israel dramatically intensified its airstrikes in Lebanon this week, saying it is determined to put an end to more than 11 months of Hezbollah fire into its territory. The escalated campaign has killed more than 720 people in Lebanon, including dozens of women and children, according to Health Ministry statistics. A predawn strike on Friday in the mainly Sunni border town of Chebaa killed nine members of the same family, the state news agency said.

Iranian-backed Hezbollah, the strongest armed force in Lebanon, began firing rockets into Israel almost immediately after Hamas’ October 7 attack, saying it was a show of support for the Palestinians. Since then, it and the Israeli military have traded fire almost daily, forcing tens of thousands of people to flee their homes on both sides of the border.

An Israeli security official said he expected the campaign against Hezbollah would not last for as long as the current war in Gaza because the military’s goals were much narrower.

In Gaza, Israel aims to dismantle Hamas’ military and political regime, but the goal in Lebanon is to push Hezbollah away from the border – “not a high bar like Gaza” in terms of operational objectives, said the official, who spoke on the condition of anonymity due to military briefing guidelines.

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The Israeli military said it carried out dozens of strikes around the south on Friday, targeting Hezbollah rocket launchers and infrastructure. It said Hezbollah fired a volley of rockets toward the northern Israeli city of Tiberias.

In the southern Lebanese city of Tyre, civil defence workers pulled the bodies of two women – 35-year-old Hiba Ataya and her mother Sabah Olyan – from the rubble of a building brought down by a strike.

“That’s Sabah, these are her clothes, my love,” one man cried out as her body emerged.

Israel says its accelerated strikes this week have already inflicted heavy damage on Hezbollah’s weapons capabilities and its fighters. But the group boasted a large arsenal of rockets and missiles and its remaining capacities remain unknown.

Hezbollah officials and their supporters remain defiant. Not long before the explosions on Friday evening, thousands massed in another part of Beirut’s suburbs for the funeral of three Hezbollah members killed in earlier strikes, including the head of the group’s drone unit, Mohammed Surour.

Men and women in the giant crowd waved their fists in the air and chanted, “We will never accept humiliation” as they marched behind the three coffins, wrapped in the group’s yellow flag.

Hussein Fadlallah, Hezbollah’s top official in Beirut, said in a speech that no matter how many commanders Israel kills, the group has endless numbers of experienced fighters. He vowed that Hezbollah will keep fighting until Israel stops its offensive in Gaza.

“We will not abandon the support of Palestine, Jerusalem and oppressed Gaza,” Fadlallah said. “There is no place for neutrality in this battle.”

Reuters and AP

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