Israel's military on Wednesday said it killed senior Hezbollah commander Haj Youssef Ismail Hashem in the biggest blow to the group since a fresh bout of fighting with Israel erupted early last month.

Israel's navy killed Hashem, the commander of Hezbollah's southern front, the country's military spokesperson Avichay Adraee said in a statement on X. Hezbollah later confirmed his death in a statement Wednesday, calling him a "beacon of the Islamic Resistance."

His death is considered one of the biggest setbacks suffered by the group since the killing of chief of staff Haytham Ali Tabtabai in November 2025.

Hezbollah, which is backed by Iran, has lost most of its senior commanders following its last war with Israel that raged from October 2023 to November 2024. Hashem had inherited his position from Ali Karaki, killed alongside the group's former leader Hassan Nasrallah in an Israeli attack on September 2024.

"He is a tier-one commander and this is the harshest blow we have been subject to since the assassination of Tabtabai," a senior Hezbollah official told Reuters.

Haytham Ali Tabtabai was appointed as chief of staff following the group's 2024 war with Israel. He was killed on the outskirts of the capital Beirut in an operation that had targeted the group after it struck a ceasefire deal with Israel that brought an end to the fighting. The pause in violence proved short-lived.

Throughout the ceasefire Israel targeted Hezbollah commanders and operatives across Lebanon. Fighting reignited early last month after Hezbollah launched rockets at Israel prompting a retaliation that expanded into an all-out war.

Since then, more than 1.2 million people have been displaced from their homes in Lebanon and Israeli attacks have killed more than 1,260 people, according to Lebanese authorities.

More than 400 fighters from Hezbollah have been killed since March 2, two sources familiar with Hezbollah's count told Reuters.

Ten Israeli troops have been killed in southern Lebanon since March 2, the Israeli military has said.

Israel's attack targeting Hashem killed seven people and wounded 26 others, according to Lebanese authorities.

Hashem was meeting with senior commanders when he was killed, the official said.

".. a team was monitoring the sky for drones or war (planes) and the strike came from warships, and that had not been accounted for," the source added. "A group of second-tier and third-tier commanders and some escorts were killed alongside him."

Talal Atrissi, a sociology professor at the Lebanese University and an analyst who is close to Hezbollah, said Hashem's killing is unlikely to affect the group's conduct on the battlefield. "It is of course a loss for Hezbollah and the resistance, but of course as we have seen, they have a number two and a number three that they can replace him with," he said.