The Israeli military said it had targeted Hezbollah's central headquarters in Beirut's southern suburbs on Friday in an attack that shook the Lebanese capital and sent thick clouds of smoke over the city.
The news outlet Axios cited an Israeli source as saying Hezbollah leader Sayyed Hassan Nasrallah was the target of the strike and that the Israeli military was checking if he was hit.
Hezbollah's al-Manar television reported that four buildings were destroyed and there were many casualties in the multiple strikes, which marked a major escalation of Israel's conflict with the group.
The Israeli military said it had carried out a "precise strike" on Hezbollah's headquarters which it said were embedded under residential buildings.
Israel has struck the Hezbollah-controlled southern suburbs of Beirut, known as Dahiyeh, four times over the last week, killing at least three senior Hezbollah military commanders.
But Friday's attack was far more powerful, with multiple blasts shaking windows across the city, recalling Israeli airstrikes during the war it fought with Hezbollah in 2006.
The strikes hit Beirut shortly after Israeli Prime Minister Benjamin Netanyahu vowed to continue Israel's attacks on Iranian-backed fighters in Lebanon in a closely watched United Nations speech, as hopes faded for a ceasefire.
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