Hezbollah leader Hassan Nasrallah killed by Israel in major escalation of conflict

Hezbollah’s veteran leader, Sayyed Hassan Nasrallah, who led the group for more than three decades, has been killed by Israel in a series of strikes on the group’s underground headquarters in Beirut, Israel and Hezbollah have confirmed.

The announcement by the Israel Defense Forces (IDF) on Saturday morning came after overnight speculation about the fate of Nasrallah, following the strikes in Dahieh, a southern suburb of the Lebanese capital, on Friday.

Later on Saturday, Hezbollah, which is backed by Iran, confirmed his death, saying Nasrallah “had joined his fellow martyrs”. It added that the group would “continue the holy war against the enemy and in support of Palestine”.

The statement, however, did not mention who would succeed Nasrallah, or how the group would respond to the assassination.

Gunfire could be heard across Beirut on Saturday afternoon as mourners fired in the air to commemorate his death and fears grew over further escalation.

Iran’s supreme leader, Ayatollah Ali Khamenei, announced five days of mourning late on Saturday and declared that Nasrallah’s blood “will not go unavenged”. Iran has so far been reluctant to involve itself in the fighting between the Lebanon-based group and Israel.

Israel meanwhile continued air strikes on Lebanon on Saturday, saying it had hit a Hezbollah target in Beirut’s southern suburbs, and Hezbollah said it had fired rockets at Israel. The Israeli military also said it had intercepted a missile fired from Yemen at Tel Aviv, in what appeared to be an attack by Houthi rebels shortly the Israeli prime minister, Benjamin Netanyahu returned from New York.

The killing marks a major moment in the crisis in the Middle East and threatens to reshape the course of events in the region where Nasrallah was a significant actor.

Iran considers Hezbollah to be one of its most significant assets. Khamenei , who Reuters reported had been transferred to a secure location inside Iran, had earlier called on Muslims “to stand by the people of Lebanon and the proud Hezbollah with whatever means they have and assist them in confronting the … wicked regime [of Israel]”.

The US defence secretary, Lloyd Austin, told his Israeli counterpart, Yoav Gallant, that said the US was determined to prevent Iran or Iran-backed groups from expanding the conflict and was committed to the defence of Israel, the Pentagon said. Russia condemned the killing of Nasrallah as “political murder” and called on Israel to stop hostilities in Lebanon.

Iranian state media on Saturday also announced the death of a prominent Revolutionary Guards general in the strike. Abbas Nilforushan, 58, was sanctioned by the US in 2022 for his role in suppressing protests after the death of Mahsa Amini, who had been arrested by Iran’s morality police for not wearing a headscarf correctly,

According to sources in Israel, the Israeli security cabinet had previously pulled back from plans to kill Nasrallah, but having established that he was due to attend a meeting at the command complex, approved a plan to kill him in an operation reportedly codenamed “New Order”.

Reports in the Israeli media said the assassination had been carried out by a squadron of F15I jets equipped with bunker-busting bombs although Israel refused to comment on claims they were US-supplied type 84 munitions.

Related: To understand the escalation in Lebanon, we must confront what Israelis are thinking | John Jenkins

The news was initially broken by the military spokesperson Lt Col Nadav Shoshani in a brief post on X saying: “Hassan Nasrallah is dead.” In a statement issued shortly afterwards, the IDF said Nasrallah had been killed along with Hezbollah’s southern front commander, Ali Karki, and other commanders attending the meeting.

“Following precise intelligence from the IDF and the Israeli security establishment, IAF [Israeli air force] fighter jets conducted a targeted strike on the central headquarters of the Hezbollah terrorist organisation which was located underground, embedded under a residential building in the Dahieh area of Beirut,” the statement said.

“The strike was conducted while Hezbollah’s senior chain of command was operating from the headquarters and advancing terrorist activities against citizens of the state of Israel.”

The Israeli military said it was on “high alert” and prepared for a wider escalation.

Shoshani later predicted that Hezbollah would continue to target Israel. “We’ve seen Hezbollah carry out attacks against us for a year. It’s safe to assume that they are going to continue carrying out their attacks against us, or try to,” he said.

After Israel’s announcement, the streets of Beirut emptied. Storefronts in Gemayzeh – an upmarket neighbourhood in east Beirut – were mostly closed.

The Lebanese army deployed throughout Beirut on Saturday afternoon, standing guard at major intersections throughout the city, probably in anticipation of public reaction. Lines formed at supermarkets as people rushed to buy basic goods, such as water and dried foods, while people waited in queues at cash machines. Low-flying Israeli patrol drones buzzed overhead throughout the day.

Lebanon’s cabinet announced it would convene for an extraordinary session at 7.30pm local time in response to the events of the last two days.

In Dahieh, one resident told the Guardian: “I’m in despair, I don’t know what to feel.” Other supporters of Hezbollah struck a different tone. “The group will go on, it’s not just centred around one leader,” Fatimah, a resident of Dahieh, said from her car in downtown Beirut where she has been sleeping with her husband and son since the strikes on Dahieh started last week.

Hezbollah’s second in command, Hashem Safieddine, who could succeed Nasrallah, was reportedly also targeted in Friday’s airstrike.

The IDF’s chief of staff, Herzi Halevi, said on Saturday that the elimination of Nasrallah was “not the end of our toolbox”, indicating that more strikes were planned. He said the strike targeting the Hezbollah leadership was the result of a long period of preparation.

The military said it was mobilising additional reserve soldiers as tensions escalated with Lebanon, activating three battalions of reserve soldiers to serve across Israel. It sent two brigades to northern Israel earlier in the week to train for a possible ground invasion.

Shortly before the strike, Netanyahu, vowed during a speech at the UN general assembly to keep fighting in Lebanon, crushing hopes that Israel would agree to a 21-day truce proposed by the US and France.

Related: Hassan Nasrallah: the man who has led Hezbollah to the brink of war with Israel

“There is no place in Iran that the long arm of Israel cannot reach, and that is true of the entire Middle East,” Netanyahu said in New York.

Among Hezbollah’s constituents, Nasrallah was viewed with a prophet-like fervour, seen as the liberator of south Lebanon from Israel’s 18-year occupation. At Hezbollah rallies, supporters chant “ Labaik ya Hussein and Labaik ya Nasrallah” – “O Hussein, O Nasrallah, I am here for you” – shouting their devotion to Hussein, a key figure in Shia Islam, and Nasrallah.

When Nasrallah spoke in televised addresses, supporters would tune in for guidance on political, spiritual and cultural issues. Many Lebanese people attribute the failure of the 2019 revolution to a speech by Nasrallah, when he told his supporters it was time to get off the streets, depriving the protest movement of its non-sectarian character.

Whoever replaces the enigmatic former secretary general will have to deal with an organisation that over the last year, has lost almost every senior military leader and is on the back foot from the Israeli bombing campaign .

The death also throws the fate of the Lebanese state into question. Hezbollah is deeply embedded in the state, controlling a key share of parliament and exercising influence over several ministries, such as the directorate of general security. Lebanon’s foreign policy is largely dictated by the group, particularly when it comes to neighbouring states such as Israel.

Hezbollah began firing into Israel one day after Hamas’s 7 October attack on southern Israel that sparked the war in Gaza.

Israel has in recent days shifted the focus of its operation from Gaza to Lebanon, where heavy bombing has killed more than 700 people and displaced about 118,000.