The militant group targeted areas in Israel farther south than most of its previous attacks, reinforcing fears of broader regional conflict.

The overnight rocket barrage was in response to Israeli attacks in Lebanon that have killed dozens, including a veteran Hezbollah commander, and an unprecedented attack targeting the group’s communications devices.

NAHARIYA, Israel — Hezbollah launched more than 100 rockets early Sunday across northern Israel, with some landing near the city of Haifa, as Israel launched hundreds of strikes on Lebanon. A Hezbollah leader declared an “open-ended battle” was underway as both sides appeared to be spiraling closer toward all-out war.