Hezbollah Chief Hassan Nasrallah, 64-year-old, was killed in a strike in Beirut on Saturday.
An unnamed source close to Lebanon's Hezbollah group told news agency AFP that contact had been lost since last evening with chief Hassan Nasrallah.
Military spokesman Lieutenant Colonel Nadav Shoshani declared on X that "Hassan Nasrallah is dead."
After Hezbollah fired numerous rockets into northern Israel, the Israelis launched attacks that targeted dozens of their locations in eastern and southern Lebanon. Overnight, Israeli jets destroyed multiple residential buildings in southern Beirut by bombarding Hezbollah strongholds.
"Hassan Nasrallah will no longer be able to terrorise the world," the Israel Defence Forces (IDF) said in a statement.
"This is not the end of our toolbox. The message is simple, anyone who threatens the citizens of Israel -- we will know how to reach them," Lieutenant General Herzi Halevi said in a statement.
This series of retaliatory strikes came just hours after Hezbollah claimed credit for shooting missiles into northern Israel. One such strike, with Fadi-1 rockets, targeted the kibbutz Kabri, which Hezbollah said was in defence of Lebanon against Israeli "barbaric" aggression.
Nasrallah, who holds immense power in Lebanon, particularly among his Shiite supporters, is widely seen as the only figure capable of waging war or brokering peace.
According to reports, the 64-year-old's daughter Zainab was killed in one of the airstrikes targeting Hezbollah strongholds in southern Beirut, however, there has been no confirmation from Hezbollah or Lebanese media.
Nasrallah was rumoured to have been killed in 2006 following Israel's invasion of Lebanon. However, the Shiite leader reemerged days later unhurt. The Israeli strikes also killed Ali Karake, commander of Hezbollah's southern front, and other Hezbollah members.
“During Hassan Nasrallah's 32-year reign as the Secretary-General of Hezbollah, he was responsible for the murder of many Israeli civilians and soldiers, and the planning and execution of thousands of terrorist activities," an Israeli statement read. "He was responsible for directing and executing terrorist attacks around the world in which civilians of various nationalities were murdered. Nasrallah was the central decision-maker and the strategic leader of the organisation." also added.
Air raid sirens were blasted throughout northern Israel, indicating an imminent threat from rockets launched across the Lebanese border. According to Israeli military accounts, two surface-to-surface missiles were fired from Lebanon, one of which fell in an open region and the other intercepted.
Lebanon's health ministry has ordered the evacuation of hospitals in Beirut's southern suburbs, preparing for further escalation. The ministry advised unaffected hospitals to halt admitting non-emergency patients to make way for those being moved from crisis zones.
The Israeli bombing of Lebanon has killed more than 700 people and displaced around 118,000.
