The Hezbollah leader was outside his home in the Bekaa valley when unidentified gunmen arrived in two vehicles, opened fire on Hamadi, killing him on spot.
Hezbollah, one of Lebanon's most powerful political players, has been significantly weakened by its conflict with Israel.
Hezbollah commander Sheikh Muhammad Ali Hammadi, a fugitive on the FBI's most-wanted list, was shot dead in eastern Lebanon.
Husainy, a Muslim cleric from Michigan, was reportedly tapped to deliver a benediction at President-elect Trump's inauguration after a series of controversial remarks.
Masked men arrived at the house of Hezbollah's leader of the Western Beqaa Valley, Mohammed Hamada, and shot him four times • Their identities remain unknown
President Joe Biden confused Palestinian militant group Hamas with Hezbollah while announcing a ceasefire to the Israel-Hamas war on Wednesday.
In Lebanon, many saw the election on Thursday of Gen. Joseph Aoun, the commander of the Lebanese military, as a crucial step toward bringing stability to the country. It was also seen as a concession by Hezbollah and, some analysts said, an acknowledgment that the group was no longer in a position to paralyze the state.
A Dearborn imam who had been set to deliver a benediction at President Donald Trump's inauguration Monday was left out of the program.
The Lebanese parliament finally voted on a new president on Thursday following two years of deadlock. Joseph Aoun the head of the country's armed forces won a majority of the votes.
Senior Hezbollah lawmaker Mohammed Raad said on Monday the Iran-backed group's opponents were seeking its fragmentation and exclusion from power in Lebanon.
Israeli war planes struck Hezbollah targets in Lebanon, the Israel Defense Force said early Monday, as it accused the truce monitoring mechanism of ignoring the threat the targets posed to Israel.