JERUSALEM/GAZA, March 18 (Xinhua) -- Israel carried out deadly bombardments across the Gaza Strip early Tuesday, killing more than 400 people, as it vowed to intensify attacks if Hamas did not release the hostages still held in the enclave.

The surprise airstrikes began overnight amid indirect negotiations between Israel and Hamas regarding the next steps of a truce, which could include ending the war and releasing the remaining Israeli hostages. The strikes broke nearly two months of ceasefire and raised fears of fully reigniting the 17-month war.

HIGH CASUALTIES AFTER SURPRISE ATTACKS

Gaza's health authorities said the death toll from the strikes had risen to at least 413, adding that many victims remained trapped under the rubble of collapsed buildings.

According to the Hamas-run Gaza government media office, the Israeli strikes targeted densely populated residential areas across the south, north, and center of the Strip, as well as camps for displaced persons.

"Women, children, and the elderly make up the majority of the victims," the media office said.

Local eyewitnesses described scenes of devastation in crowded neighborhoods, with Israeli fighter jets and drones circling overhead.

At least five senior officials and their families were among the dead, according to security sources in the Hamas government.

The officials killed included Issam al-Daalis, a member of Hamas's political bureau and head of the Government Follow-up Committee in Gaza; Ahmed Omar al-Hatta, deputy minister of Hamas's justice ministry; Mahmoud Abu Watfa, Hamas's deputy interior minister; Bahjat Hassan Abu Sultan, director-general of Hamas's internal security service; and Abu Obeida al-Jamasi, a political bureau member and head of the emergency committee in Gaza, the sources said.

After the deadly attacks, the Israeli army issued evacuation orders, prompting Palestinians to flee in chaos. Israeli military's Arabic-language spokesperson, Avichay Adraee, called on civilians to move west.

A map he posted on social media platform X marked in red the entire perimeter around Gaza, designating it as a "dangerous combat zone." The targeted areas included the city of Beit Hanoun, the town of Khuza'a, and the Abasan suburbs of Khan Younis.

"As of this morning, Israel is operating with full force against Hamas in Gaza," Israeli Foreign Ministry spokesperson Oren Marmorstein said in an official statement Tuesday morning.

He said the attacks aimed to achieve the war's objectives, including "the release of all our hostages, the dismantling of Hamas's military and governmental infrastructure, and the removal of the terrorist threat from Gaza to Israel's security and its citizens."

"From this point forward, Israel will act against Hamas with increasing military intensity," Marmorstein added.

In a press statement, Hamas accused Israeli Prime Minister Benjamin Netanyahu and his government of deliberately violating the ceasefire agreement and escalating the conflict.

"Netanyahu and his extremist government have decided to overturn the ceasefire and expose prisoners in Gaza to an unknown fate," Hamas said.

Philip Lazzarini, head of the United Nations Relief and Works Agency for Palestine Refugees (UNRWA), urged an immediate return to the ceasefire. "Fueling 'hell on earth' by resuming the war will only bring more despair and suffering," he wrote on X.

Lazzarini cited "awful scenes of civilians killed, among them children, following waves of heavy bombardment from Israeli forces overnight."

Israeli Prime Minister Benjamin Netanyahu said he authorized the first major strikes since the ceasefire took effect on Jan. 19 because Hamas refused "to release our hostages."

INTERNATIONAL REACTIONS

Iran on Tuesday condemned Israel's latest airstrikes on the Gaza Strip, blaming the United States for what it described as ongoing atrocities in the Palestinian territories.

Iranian Foreign Ministry spokesperson Esmaeil Baghaei said Washington bore "direct responsibility for the continuation of genocide in the occupied Palestinian territories."

Egypt also denounced the strikes, calling them a "flagrant violation of the ceasefire agreement" and a "dangerous escalation" that threatened regional stability.

"The attacks undermine efforts to restore calm and stability," Egypt's Foreign Ministry said in a statement. It urged the international community to "intervene immediately to halt the Israeli aggression" and prevent further violence.

The Turkish Foreign Ministry on Tuesday condemned Israel's latest attack, saying the renewed violence "defies humanity through its violations of international law and universal values in the gravest way."

UN High Commissioner for Human Rights Volker Turk said he was "horrified" by the renewed airstrikes, warning that continued military action would worsen conditions for Gaza's population.

"It is abundantly clear that there is no military path out of this crisis," Trk said in a statement from Geneva. "The only way forward is a political settlement in line with international law."

European Union aid commissioner Hadja Lahbib also called for an immediate cessation of hostilities.

"The renewed escalation in Gaza is devastating. Civilians have endured unimaginable suffering. This must stop," Lahbib wrote on X, urging a swift return to a ceasefire.

CEASEFIRE COLLAPSE

The first phase of the ceasefire ended on March 1. Under the terms of the deal, in the second phase, Israel was supposed to have completely withdrawn its forces, and Hamas was expected to release the remaining hostages. Instead, Israel sought to extend the first phase, calling on Hamas to release an additional 11 hostages in exchange for Palestinian prisoners. Hamas, for its part, insisted on continuing the implementation of the original agreement. Mediated talks over the next stages of the ceasefire continued through Qatar, Egypt, and the United States, but no agreement was reached.

A total of 59 hostages remain held in Gaza, with Israeli authorities estimating that fewer than half are still alive. During the first phase of the ceasefire, 33 Israeli hostages and five Thai nationals were released in exchange for some 2,000 Palestinian prisoners.

The massive airstrikes triggered anxiety and fear among the hostages' families. The Hostages and Missing Families Forum, representing the hostages' relatives, issued an "urgent call," stating that the decision to resume assaults put their loved ones "in grave danger."

Israel prepared for possible Hamas retaliation, with the Home Front Command announcing the cancellation of schools in communities near Gaza. Train services to the southern city of Sderot were also temporarily halted.