Israel bombed the center of Beirut for the first time in almost a year of hostilities with Lebanon’s Hezbollah, as the military steps up air assaults following the killing of the Iran-backed group’s chief last week.

Hezbollah confirmed Saturday its longtime leader Hassan Nasrallah—the target of Israel’s aerial bombardment on the group’s Beirut headquarters—was killed during the strike, a major victory for Israel but a further escalation in the conflict.