NAHARIYA, Israel>> Hezbollah fired 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.

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. Air raid sirens across northern Israel sent hundreds of thousands of people scrambling into shelters.

One struck near a residential building in Kiryat Bialik, a city near Haifa, wounding at least three people and setting buildings and cars ablaze.

Israel’s Magen David Adom rescue service said four people were wounded.

Avi Vazana raced to a shelter with his wife and 9-month-old baby before he heard the rocket hitting. Then he went back outside to see if anyone was hurt.“I ran without shoes, without a shirt, only with pants. I ran to this house when everything was still on fire to try to find if there are other people,” he said.

Lebanon’s Health Ministry said three people were killed and four wounded in Israeli strikes near the border.

The rocket attacks followed an Israeli airstrike Friday in Beirut that killed at least 45 people, including Ibrahim Akil, one of Hezbollah’s top leaders, several other fighters, and women and children.

Hezbollah was already reeling from a sophisticated attack that caused thousands of pagers and walkie-talkies to explode just days earlier. But it faces a difficult balance of stretching the rules of engagement by hitting deeper into Israel, while at the same time trying to avoid large-scale attacks on civilian areas and infrastructure that could trigger a full-scale war that it would rather not start and take the blame for. Hezbollah’s deputy leader Naim Kassem said Sunday’s rocket attack was just the beginning of what’s now an “open-ended battle” with Israel.

“We admit that we are pained. We are humans. But as we are pained — you will also be pained,” Kassem said at Akil’s funeral. He vowed Hezbollah will continue military operations against Israel in support of Gaza but also warned of unexpected attacks “from outside the box,” pointing to rockets fired deeper into Israel.

Late Sunday night, Hezbollah announced a series of strikes on military sites in northern Israel with missiles and artillery shelling. It was not immediately clear if there were any casualties or damages.

Prime Minister Benjamin Netanyahu said Israel would take whatever action was necessary to restore security in the north and allow people to return to their homes.

“No country can accept the wanton rocketing of its cities. We can’t accept it either,” he said.

Other funerals were held Sunday for those killed in the airstrike. Seven people, including three women and two children, were buried in the southern Lebanese town of Mays al-Jabal, where Christian Lebanese lawmaker Melhem Khalaf said Israel “relies on the laws of the jungle instead international conventions, especially with protecting civilians.”

White House national security spokesman John Kirby told ABC’s “This Week” that the U.S. has been “involved in extensive and quite assertive diplomacy.” He added: “We want to make sure that we can continue to do everything we can to try to prevent this from becoming an all-out war there with Hezbollah across that Lebanese border.”

The Israeli military said it struck about 400 militant sites, including rocket launchers, across southern Lebanon in the past 24 hours.

“Hundreds of thousands of civilians have come under fire across a lot of northern Israel,” said Israeli military spokesman Lt. Col. Nadav Shoshani. “Today we saw fire that was deeper into Israel than before.”