THE HAGUE, Netherlands >> In a case that strikes at the heart of Israel’s national identity, South Africa formally accused the country of committing genocide against Palestinians and pleaded Thursday with the United Nations’ top court to order an immediate halt to Israeli military operations in Gaza.

Israel, which was founded in the aftermath of the Holocaust, has vehemently denied the allegations. As a sign of how seriously they regard the case, Israeli leaders have taken the rare step of engaging with the court to defend their international reputation. Israel often boycotts international tribunals or U.N. investigations, saying they are unfair and biased.

During opening statements at the International Court of Justice, South African lawyers said the latest Gaza war is part of decades of Israeli oppression of Palestinians.

The court “has the benefit of the past 13 weeks of evidence that shows incontrovertibly a pattern of conduct and related intention” that amounts to “a plausible claim of genocidal acts,” South African lawyer Adila Hassim told the judges and audience in a packed room of the Peace Palace in The Hague.

Prime Minister Benjamin Netanyahu blasted the case and vowed to continue fighting Hamas, the militant group whose fighters stormed through Israeli communities on Oct. 7 and killed some 1,200 people, mainly civilians.

“This is an upside-down world — the state of Israel is accused of genocide while it is fighting genocide,” he said in video statement. “The hypocrisy of South Africa screams to the heavens.”

The case is one of the most significant ever heard in an international court, and it goes to the core of one of the world’s most intractable conflicts.

South Africa is seeking preliminary orders to compel Israel to stop its military campaign in Gaza, where more than 23,000 people have died, according to the Health Ministry in the territory, which is run by Hamas.

“Nothing will stop the suffering except an order from this court,” Hassim said.

A decision on South Africa’s request for so-called provisional measures will probably take weeks. The full case is likely to last years.

Israel launched its massive air and ground assault on Gaza soon after the deadly Hamas attack. Three months later, the offensive has driven nearly 85% of Gaza’s population of 2.3 million from their homes. With only a trickle of food, water, medicine and other supplies entering through an Israeli siege, a quarter of the territory’s residents face starvation. And much of northern Gaza, including Gaza City, has been reduced to a moonscape.

Although the court’s findings are considered binding, it was unclear whether Israel would heed any order to halt the fighting. If it doesn’t, it could face U.N. sanctions, although those may be blocked by a U.S. veto.

The White House declined to comment on how it might respond if the court determines Israel committed genocide. But National Security Council spokesman John Kirby called the allegations “unfounded.”

“That’s not a word that ought to be thrown around lightly, and we certainly don’t believe that it applies here,” Kirby said.

Israel says it is battling a fierce enemy that carried out the deadliest attack on its territory since its creation in 1948. Israeli leaders insist they are following international law and doing their utmost to avoid harm to civilians. The country blames Hamas for the high death toll, saying its enemy operates in residential areas.

In a post on X after the hearing, Israeli Foreign Ministry spokesman Lior Haiat called South Africa’s presentation “one of the greatest shows of hypocrisy” and referred to the legal team as “Hamas’ representatives in court.” He said South African lawyers distorted the reality in Gaza through a series of “baseless and false claims.” He did not elaborate.

That reaction came after South Africa insisted Israel committed genocide by design.

“The scale of destruction in Gaza, the targeting of family homes and civilians, the war being a war on children, all make clear that genocidal intent is both understood and has been put into practice. The articulated intent is the destruction of Palestinian life,” said lawyer Tembeka Ngcukaitobi.

He said the case’s “distinctive feature” was “the reiteration and repetition of genocidal speech throughout every sphere of the state in Israel.”

The Oct. 7 attackers also abducted around 250 people, nearly half of whom have been released. Ahead of the proceedings, hundreds of pro-Israeli protesters marched close to the courthouse with banners saying “Bring them home,” referring to the hostages still being held by Hamas.

One of the Israeli protesters was Michael Nevy, 42, whose brother was kidnapped by Hamas. “People are talking about what Israel is doing, but Hamas is committing crime against humanity every day,” he said.

At a separate demonstration nearby, pro-Palestinian protesters waved flags calling for an end to “Israeli apartheid” and the adoption of a cease-fire.

Chanting by protesters on the streets around the court’s manicured grounds could sometimes be heard in the courtroom.

The case targets the center of Israeli identity and the country’s creation as a Jewish state in the aftermath of the Nazi Holocaust, which killed 6 million Jews.

It also evokes issues central to South Africa’s own identity: Its governing party, the African National Congress, has long compared Israel’s policies in Gaza and the West Bank to its own history under the apartheid regime of white minority rule, which restricted most Blacks to “homelands” before ending in 1994.

The two-day hearing continues Friday, when Israel, which has sent a strong legal team to make its defense, is scheduled to address the court.

South Africa sought to broaden the case beyond the Israel-Hamas war.

“The violence and the destruction in Palestine and Israel did not begin on Oct. 7, 2023. The Palestinians have experienced systematic oppression and violence for the last 76 years,” said South African Justice Minister Ronald Lamola.

About two-thirds of the dead in Gaza are women and children, health officials there say. The death toll does not distinguish between combatants and civilians.

“Mothers, fathers, children, siblings, grandparents, aunts, cousins are often all killed together. This killing is nothing short of destruction of Palestinian life. It is inflicted deliberately. No one is spared. Not even newborn babies,” said South African lawyer Hassim.

The world court, which rules on disputes between nations, has never judged a country to be responsible for genocide. The closest it came was in 2007 when it ruled that Serbia “violated the obligation to prevent genocide” in the July 1995 massacre by Bosnian Serb forces of more than 8,000 Muslim men and boys in the Bosnian enclave of Srebrenica.

The nearby International Criminal Court prosecutes individuals for war crimes, crimes against humanity and genocide.

The case against Israel revolves around the genocide convention that was drawn up in 1948 following World War II. Both Israel and South Africa were signatories.

Israel will be back on the International Court of Justice’s docket next month, when hearings open into a U.N. request for an advisory opinion on the legality of Israeli policies in the West Bank and east Jerusalem.

Casert reported from Brussels. Associated Press journalists Gerald Imray in Cape Town, South Africa; Tia Goldenberg in Tel Aviv, Israel; Aleksandar Furtula in The Hague; and Aamer Madhani in Washington contributed to this report.