As Fighting Rages in Gaza, Israel Issues Warnings on Another Front

Street-to-street combat raged in what Israel described as three Hamas strongholds in the Gaza Strip on Monday, as top Israeli officials warned that increased attacks on northern Israel by Hezbollah, from Lebanon, could prompt a powerful response.

Fighting in “fierce and difficult battles,” the Israeli military said Monday that the number of its soldiers killed in the ground invasion of Gaza had surpassed 100 — a fraction of the death toll among Palestinian civilians and Hamas fighters, but a measure of the intensity of the urban warfare.

At the same, in a sign that the smoldering tensions inflamed across the Middle East by the war in Gaza could be heating up, Israeli leaders hinted at escalating a conflict on another front, with Hezbollah, which like Hamas is backed by Iran.

Increasing Hezbollah strikes on northern Israel “demand of Israel to remove such a threat,” Benny Gantz, a member of the war cabinet and former defense minister, told the American secretary of state, Antony J. Blinken, in a phone call, according to a statement by Mr. Gantz’s office.

The chief of staff of Israel’s military, Lt. Gen. Herzi Halevi, said on a visit to the northern border with Lebanon on Sunday that Hezbollah risked pushing his forces to make a “very clear change” in the confrontation. Neither he nor Mr. Gantz elaborated on what additional steps Israel might take, but General Halevi said that on both frontiers, Israel needs a return of “both safety and a sense of security.”

A third Iranian-backed militia, the Houthis, threatened over the weekend to step up attacks on ships bound for Israel that are transiting the Red Sea. The French Navy said on Sunday that one of its frigates there had shot down two drones launched from Yemen, where the Houthis are based.

In Gaza, the Israeli military said it had taken control of the area surrounding the former headquarters of Hamas in Gaza City, and released images showing soldiers firing barrages of gunfire as they moved tensely through nearly deserted, rubble-filled streets.

Rear Adm. Daniel Hagari, spokesman for the Israeli military, told reporters that it was focused on fighting in three areas that are Hamas strongholds: Jabaliya and Shajaiye, two neighborhoods in northern Gaza, and in Khan Younis, the largest city in southern Gaza.

Jabaliya, a densely populated area just north of Gaza City, has been struck relentlessly by Israeli forces since the first weeks of the war, including with at least two 2,000-pound bombs during one airstrike last month, according to a New York Times analysis. Israeli troops have also targeted Shajaiye, a residential area, since the start of their ground invasion.

The intense fighting came as the United Nations and aid agencies warned of what António Guterres, the U.N. secretary-general, said was chaos and the risk of epidemics in the shrinking pockets of the territory where civilians have sought refuge from Israeli bombardments.

More than 15,000 Palestinians — possibly far more — have been killed in Gaza since Israel launched its retaliatory campaign against Hamas, in response to the Oct. 7 Hamas-led raids that killed some 1,200 people in Israel. Israeli officials say their forces have killed thousands of Hamas fighters; the Gazan authorities say most of the dead have been women and children.

A number of European countries that have been vociferous in calling for a cease-fire sought to strike a balance Monday between supporting Israel’s effort to defeat Hamas and maintaining pressure on Israel to curb civilian suffering.

The European Union’s foreign ministers met Monday in Brussels to discuss sanctions against Hamas after France, Italy and Germany sent a joint letter to Josep Borrell Fontelles, the E.U.’s top diplomat, urging the bloc to “take all necessary measures” against the group.

“This implies a stronger European commitment both to combating Hamas’s infrastructure and financial support, and to isolating and delegitimizing Hamas internationally,” the ministers wrote in the letter, adding that Hamas “in no way represents the Palestinians or their legitimate aspirations.”

The United Nations estimates that 1.9 million of Gaza’s roughly 2.3 million people have been displaced from their homes, most of them crowding into parts of the south where they lack basic necessities like food, clean water and sanitation.

Aid groups have accused Israel of seeking to push the Gazans into Egypt, which Israel denies. The Egyptian government has said it will not accept Palestinian refugees.

As Israel’s war with Hamas enters its third month, Prime Minister Benjamin Netanyahu’s government is resisting mounting international pressure to wind down its military campaign.

Mr. Netanyahu said on Sunday that he had spoken recently with Chancellor Olaf Scholz of Germany, President Emmanuel Macron of France and other leaders, urging them to continue backing the Israeli war until Hamas was ousted from Gaza. “I told them you can’t support the elimination of Hamas on the one hand, and pressure us to end the war, which would prevent Hamas’s elimination,” Mr. Netanyahu told members of his cabinet in a video statement.

At home, Mr. Netanyahu’s government has faced pressure to seek at least another pause in the fighting from families of the roughly 137 hostages who were seized in the Hamas attack on Israel and remain in Gaza, although it is unclear what Hamas would demand for their release. More than 100 hostages were freed during a weeklong cease-fire that began Nov. 24, in return for the release of Palestinians being held in Israel jails.

At least 20 hostages are believed to have been killed after they were abducted, according to an Israeli government spokesman, Eylon Levy, heightening concerns for the fate of the rest. Hamas has claimed that many died in Israeli airstrikes.

The Biden administration has, for now, publicly backed the Israeli government, despite criticism, and says it has not set a deadline for Israel to end the war. On Friday, the United States vetoed a United Nations Security Council resolution calling for an immediate cease-fire.

The Israel military, which has been criticized by Mr. Macron, among others, for not clearly laying out an exit strategy, says its forces are engaged in intense battles with Hamas in areas where it said the group still had “strongholds.” The Israeli military now controls the area in Gaza City surrounding Palestine Square, home to municipal offices and the headquarters for Yahya Sinwar, Hamas’s leader in the enclave, Admiral Hagari said at a news conference late Sunday.

As of Monday, 104 Israeli soldiers have been killed since the ground invasion began in late October. In its announcements of the deaths, Israel describes its soldiers as martyrs — the same language Hamas uses when its fighters are killed.

Israel has yet to find Mr. Sinwar, who they believe is hiding in southern Gaza. Officials said last week that Israeli forces had surrounded his house in the Khan Younis region, although his location was unknown. Military officials have described him as a “mastermind” of the Oct. 7 attacks in Israel, and Admiral Hagari said that capturing or killing him was still a goal of the war.

The director of Israel’s national security council, Tzahi Hanegbi, has rejected the idea that the lives of Mr. Sinwar and other top Hamas leaders could be spared if they went into exile outside Gaza, as Yasir Arafat, the leader of the Palestine Liberation Organization, did in 1982 during an Israeli invasion of Lebanon.

“I believe that Sinwar isn’t a partner for a model of that kind,” Mr. Hanegbi told Israel’s Channel 12 in an interview that aired this past weekend. “But if we kill him, which is the intention, the leadership that succeeds him might understand that in order to be spared his fate it needs to leave the Gaza Strip humiliated, but at least to save its life.”

Reporting was contributed by Rami Nazzal, Ephrat Livni, Euan Ward, Hwaida Saad, Aurelien Breeden, Gaia Pianigiani, Ben Hubbard, Vivian Nereim and Aaron Boxerman.