Israel’s military said it killed Hezbollah’s leader, Hassan Nasrallah, in an air strike on Beirut on Friday evening.

Hezbollah, an Iran-backed militant group, has yet to comment on its leader’s whereabouts or health since the bombing.

The development, if confirmed, is a massive blow for Hezbollah, which has been attacking Israel since the start of the Israel-Hamas war in October, and for Iran. 

Nasrallah, 64, has led Hezbollah since the early 1990s and is close to Iran’s supreme leader, Ayatollah Ali Khamenei. He’s integral to Tehran’s network of proxy forces in the Middle East. Hezbollah is considered the crown jewel in what’s often referred to as Iran’s ‘axis of resistance’ against Israel and US forces in the region.

Israel has escalated its attacks on Hezbollah hugely since early last week. It’s killed several of the organization’s leading commanders in air strikes and was blamed by Hezbollah and Iran for an operation that caused thousands of pagers and walkie-talkies in Lebanon to explode, maiming many Hezbollah members.

Israel’s strikes on Lebanon have killed more than 600 this week, including 50 children, according to Lebanese authorities. Israel says its aggression is necessary to stop Hezbollah’s attacks on its territory and force the group’s fighters back from the border.

Israel targeted Nasrallah with its strike on Hezbollah’s headquarters in Lebanon’s capital. Its officials had said they believed Nasrallah was there, along with other Hezbollah commanders.

Lebanon’s Health Ministry said at least six people were killed, with the toll set to rise. The country’s media said six buildings in the densely populated Haret Hreik neighborhood were leveled, and footage showed rescue workers pulling children from under the rubble. Hezbollah responded with rocket fire across northern Israel. Sirens sounded in the city of Safed, and in Nahariya and Karmiel.

Hezbollah, like Hamas, is considered a terrorist organization by the US and has vowed to destroy Israel.

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