Israel’s military on Tuesday rejected the Palestinian allegations, and said it had exhumed corpses to try to find hostages taken by Hamas in October.

“The claim that the IDF [Israel Defence Forces] buried Palestinian bodies is baseless and unfounded,” the military said in a statement, adding that its forces returned bodies to where they had been buried, after they were examined.

“The examination was conducted in a careful manner and exclusively in places where intelligence indicated the possible presence of hostages. The examination was carried out respectfully while maintaining the dignity of the deceased.”

In early April, the World Health Organization said al-Shifa had been destroyed by an Israeli siege, leaving an “empty shell” containing many bodies.

The UN rights office on Tuesday demanded “independent, effective and transparent investigations into the deaths”.

“Given the prevailing climate of impunity, this should include international investigators,” UN rights chief Volker Turk said in a statement.

Hospitals, which are protected under international law, have repeatedly come under Israeli bombardment over more than six months of war in Gaza.

Israel has accused Palestinian militant group Hamas of using Gazan medical facilities as command centres and to hold hostages abducted during its attack inside Israel on October 7.

Hamas has denied those claims.

“Hospitals are entitled to very special protection under international humanitarian law,” Turk pointed out.

“And the intentional killing of civilians, detainees and others who are hors de combat is a war crime.”

The UN rights office said it did not have access to independent information as to what had transpired at the two hospitals.

But spokeswoman Ravina Shamdasani said efforts were under way to corroborate reports and details given by Gaza authorities.

The latter say 283 bodies were recovered from Nasser hospital, including 42 that had been identified.

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Humanitarian aid workers delivering food killed in Gaza in 'unintentional' air strike

Humanitarian aid workers delivering food killed in Gaza in 'unintentional' air strike

“Victims had reportedly been buried deep in the ground and covered with waste,” she told reporters in Geneva.

Older people, women and wounded were reportedly among the dead, she said.

Others were allegedly “found with their hands tied and stripped of their clothes”.

As for al-Shifa, the Israeli army has said around 200 Palestinians were killed during its military operation at the hospital.

Shamdasani pointed to reports indicating that this toll “may be an underestimate”.

Around 30 bodies were reported found buried in two graves in the courtyard of al-Shifa hospital.

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“And there are reports that the hands of some of these bodies were also tied,” Shamdasani said.

So far, she said, the UN “can’t corroborate the exact figures” of people killed at the two hospitals, underlining: “This is why we are stressing the need for international investigations”.

“Clearly there have been multiple bodies discovered,” she said.

The reports that some had their hands tied indicated “serious violations” of international law, she added.

“These need to be subjected to further investigation … They can’t just be more reports in this horrific war that just pass under the radar.”