Israel's military has killed a senior member of the militant group Hezbollah in an air strike on the southern suburbs of the Lebanese capital, Beirut, despite a ceasefire.

It described Haitham Ali al-Tabtabai, Hezbollah's chief of staff, as a veteran of the group who had held a series of senior positions.

Lebanon's health ministry reported that at least five people were killed and 28 others were wounded in the strike, which targeted an apartment building in the densely populated Dahieh district.

Hezbollah confirmed Tabtabai's death, asserting that Israel had crossed a 'red line' with this attack.

The strike is Israel's first on southern Beirut for months and comes during an escalation in military activities against Hezbollah, a Shia Muslim group backed by Iran. This intensification is occurring despite a ceasefire brokered by the US and France that came into effect last November.

Israeli officials argue that Hezbollah has been attempting to enhance its military capabilities, with allegations of weapon smuggling and increased drone production.

After the airstrike, Israeli Prime Minister Benjamin Netanyahu asserted that Israel would not permit Hezbollah to regain its strength or pose a threat to the nation.

Simultaneously, Lebanon's President Joseph Aoun appealed for international pressure on Israel to halt its attacks and withdraw from occupied territories, stressing that such actions violate the peace agreement that followed a previous conflict.

While the Lebanese government has committed to disarm Hezbollah, the group refuses to negotiate its weaponry until attacks cease and prisoners are released.

This aerial conflict was reignited when Hezbollah began rocket attacks in solidarity with Palestinians following Hamas assaults on October 7, 2023, marking a significant escalation in regional violence.

Estimates from Lebanese authorities indicate that Israeli actions have resulted in about 4,000 civilian casualties and the displacement of over 1.2 million residents.

Haitham Ali al-Tabtabai was previously designated a terrorist by the US government, and a $5 million reward was offered for information leading to his capture.

Al-Tabtabai was regarded as a crucial military leader for Hezbollah, having commanded operations in Syria and Yemen, contributing to the group's destabilizing activities in the region.