Nasrallah, 64, had been at the helm of the militant Lebanese group for 32 years. His cousin Hashem Safieddine is among the frontrunners to take over.

Nasrallah's younger cousin was born in the southern Lebanese village of Deir Qanoun En Nahr near Tyre in 1960.

The young men studied theology together at two Shia institutions - one in Najaf, Iraq and the other in Qom, Iran.

They are seen from their supporters to be from a well-respected Shia family that has produced both religious scholars and Lebanese politicians.

Safieddine's brother is Hezbollah's representative to Iran, while his son is married to the daughter of Qassem Soleimani - the Iranian general killed in a US drone strike during Donald Trump's presidency in 2020.

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Like his cousin, Safieddine joined Hezbollah soon after it was set up in the early 1980s.

He also wears a black turban, as Nasrallah did, denoting being a direct descendant from the Prophet Muhammad.

Safieddine's family ties and his close resemblance to his late cousin will likely help his leadership bid, experts say.

He is already the head of Hezbollah's Jihad council and among the top members of its Shura council.

Known for his militant views, he is in charge of the group's political affairs.

At a recent event in Dahieh, where this week's airstrikes took place, he said in support of Hamas in Gaza: "Our history, our guns and our rockets are with you."

And at a funeral of one of his fellow commanders in June he appeared to threaten further escalation of the conflict with Israel, declaring: "Let [the enemy] prepare himself to cry and wail."

The US designated Safieddine a terrorist in 2017. Saudi Arabia also classifies him as a terrorist.

He has always been a vocal critic of US policy, declaring that year: "This mentally impeded, crazy US administration headed by Trump will not be able to harm the resistance."