The Israeli military was preparing to expand strikes across Lebanon early on Monday, as the long-simmering conflict with Hezbollah threatened to explode into larger war.

JERUSALEM — The Israeli military said it struck 300 targets Monday in Lebanon in one of the most intense barrages of airstrikes in nearly a year of fighting against the Hezbollah militant group.

Israel carried out hundreds of airstrikes in southern Lebanon on Monday, killing at least 100 people, as the Israeli military called on residents to immediately evacuate places where it claimed