GENEVA/JERUSALEM/GAZA/UNITED NATIONS - A UN commission on Tuesday concluded that Israel is committing genocide against Palestinians in the Gaza Strip, urging Israel to immediately cease its atrocities in the Palestinian enclave.

The Israeli authorities and security forces have committed four of the five acts of genocide, including killing, causing serious physical and mental harm, deliberately destroying the living conditions, and implementing measures aimed at preventing fertility, the UN Independent International Commission of Inquiry on the Occupied Palestinian Territory, including East Jerusalem, and Israel said in a report.

The top Israeli authorities bear responsibility for the atrocities in the Gaza Strip by planning a genocidal campaign for nearly two years with the clear intention of destroying the Palestinian community in the area, said Navi Pillay, chair of the commission.

Pillay said that Israel had continued its strategy of eliminating Palestinians in Gaza, blatantly ignoring warnings from the international community and the mandate of the International Court of Justice for interim measures.

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"The Commission finds that the Israeli authorities had no intention to change their course of actions," she said, urging the Israeli government to comply immediately with its international legal obligations, including halting the genocide, ending the hunger policy and lifting the blockade on the Gaza Strip to allow the entry of humanitarian aid.

It also called on its member states to stop transferring arms and other equipment to be used for the Israeli crimes in Gaza, and take action against individuals or corporations that are involved in the genocide.

On the same day, the Israeli foreign ministry rejected the report, calling it "fake" and accusing the authors of being "Hamas proxies".

"The report relies entirely on Hamas falsehoods, laundered and repeated by others," the ministry said.

Israeli Prime Minister Benjamin Netanyahu said on Tuesday that Israel has launched an "intense operation" in Gaza City.

Video footage on social media showed heavy bombardment by aircraft and artillery, with flares and fires rising above buildings.

Local health authorities in Gaza reported that at least 37 people were killed and dozens went missing in Gaza City, with four more killed elsewhere in the enclave.

Israel's military has ramped up forces over the past weeks ahead of what Netanyahu and other officials described as a major ground and air offensive to "conquer" Gaza City, the enclave's main urban center.

IDF intensifies airstrikes

The Israeli army intensified its airstrikes on Gaza City early Tuesday in what some residents and observers described as a possible prelude to expanding ground operations inside the city, amid rising casualties and a worsening humanitarian crisis among the Gaza population.

Palestinian sources told Xinhua that warplanes and drones continuously targeted multiple neighborhoods, supported by artillery and helicopter fire, while the Israeli army said it had carried out "a series of large-scale attacks" that would "gradually increase in intensity" in the coming days.

Israeli media reported that more than 35 sites were hit, including the neighborhoods of al-Sabra, al-Daraj, Sheikh Radwan, the al-Shati refugee camp and Tal al-Hawa, with explosions reportedly heard as far away as in Jerusalem and Tel Aviv.

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Medical sources in Gaza confirmed that several Palestinians, including women, children, and the elderly, were killed in the latest strikes, while dozens more were injured.

According to the civil defense, three houses near the General Security Intersection north of Gaza City were hit, leaving multiple casualties.

"A large number of dead and missing people remain under the rubble of completely destroyed homes," Mahmoud Basal, spokesperson for Gaza's Civil Defense, told Xinhua, adding that rescue crews face severe challenges due to shortages of equipment and fuel.

Basal also confirmed that several people were killed in an airstrike on the al-Sabra neighborhood, while another strike hit a home in western Gaza, causing additional deaths and injuries.

Local residents said that the army used heavy bombs that caused widespread destruction, prompting many families to flee into the streets overnight to escape the shelling.

Meanwhile, residents said the Israeli army was creating a "ring of fire" around the Safina area in northwestern Gaza City, while troops had maintained positions near al-Sheikh Radwan pond in the north for days, without launching a large-scale ground incursion into residential districts.

Intermittent shelling was also reported in al-Mukhabarat, al-Karama, and al-Maqousi neighbourhoods northwest of Gaza City.

"Gaza is burning. The IDF (Israel Defense Forces) strikes with an iron fist at the terrorist infrastructure and IDF soldiers are fighting bravely to create the conditions for the release of the hostages and the defeat of Hamas," Israeli Defense Minister Israel Katz wrote on social media.

"We will not relent and we will not go back -- until the completion of the mission," he stressed.

Hamas said in a press statement that the Israeli army's ongoing bombardment of Gaza City, including "the shelling of residential neighborhoods, the destruction of towers, and the forced displacement of civilians," amounted to "ethnic cleansing and genocide".

"The enemy's reliance on massacres, starvation, and destruction will fail, as it has failed before," said Hamas, while holding Netanyahu "responsible for the fate of the captured soldiers in Gaza".

Offensive to take 'months'

Israeli military spokesman Effie Defrin said on Tuesday the ground offensive in Gaza City would take "months," after the assault began overnight and forced thousands more Palestinians to flee the enclave's largest urban center.

He said Israeli forces were in control of "widespread" areas of Gaza City after the operation was launched overnight, following weeks of bombardments on the city's neighborhoods of Jabalia, Zeitoun and Sheikh Radwan.

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According to figures and aerial images previously released by the Palestinian Civil Defense, much of Zeitoun has been flattened since the beginning of the operation in August, with more than 1,500 homes destroyed and no buildings left standing in the southern part of the neighborhood.

Defrin said it would take several months to seize Gaza City "and several more months, perhaps longer, to clear the city, because (Hamas) infrastructure is deep-rooted and entrenched".

He also said the military had "sufficient munitions," a day after Netanyahu warned Israel was sliding into isolation and would need to strengthen its weapons industry and reduce dependence on foreign suppliers. Several Western countries have declared full or partial arms embargoes on Israel due to the Gaza onslaught.

Rejecting a United Nations commission finding that Israel has committed genocide against Palestinians in Gaza, military's Chief of Staff Eyal Zamir issued a statement, saying the army does "our utmost to mitigate harm to civilians," and that they are acting to defeat a "terrorist organization" that wants to "eliminate the very existence of the State of Israel".

48,000 flee Gaza ground offensive

Nearly 48,000 Palestinians have fled southward in the last two days from the Israeli military's ground offensive in Gaza City, UN humanitarians said on Tuesday.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said that between mid-August and Monday, its partners observed more than 190,000 such movements, with many people traveling on foot due to the extremely high cost of transport.

OCHA said its partners, providing support to those on the move, reported that more than 1,500 people, including more than 900 children, received urgent assistance, including psychosocial aid, water and medical care.

The office said its health-related partners reported that hospitals and clinics remain under immense strain. This week, Al-Quds Hospital in Gaza City sustained damage from nearby bombardments and is now sheltering displaced families. Only three of the six UN medical points in Gaza City run by the UN relief agency remain functional.

OCHA added that the Zikim border crossing has been closed for four days. Fuel and medical missions have been called off due to insecurity, congestion and looting. Aid convoys continue to face delays and risks on the road, preventing assistance from reaching civilians who need it most.

"Despite these immense challenges and dwindling supplies, the UN and its humanitarian partners continue to deliver life-saving assistance and critical services wherever and whenever possible across the Gaza Strip," OCHA said.

Hamas slams Trump's remarks

Hamas on Tuesday criticized US President Donald Trump's remarks on the situation in Gaza and Israeli hostages, calling them "blatant bias toward Israeli propaganda" and "double standards".

The statement came in response to comments Trump made Monday on his Truth Social platform, where he accused Hamas of moving Israeli captives above ground to use them as "human shields" against Israel's military offensive.

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"I hope the leaders of Hamas know what they're getting into if they do such a thing. This is a human atrocity ... Don't let this happen, or all 'bets' are off. Release all hostages now!" Trump wrote.

In a press statement, Hamas said Trump's comments ignored the humanitarian crisis in Gaza.

The group also accused Netanyahu of "undermining all chances of reaching an agreement that could lead to a halt to the war and the release of prisoners".

Hamas held the US administration responsible for "the continuation of the war as a result of its political and military support for Israel" and called on the international community and human rights organizations to "urgently intervene to stop the attacks and ensure the protection of civilians".