Turk said remains believed to belong to entire families were being recovered from sites destroyed during Israeli attacks, with many of the victims appearing to be women and children.
“It is heartbreaking that the loved ones of those missing for so long are only now having their worst fears confirmed,” he said in a statement.
He said the discoveries renewed concerns raised in a 2024 UN report that Israeli strikes on residential buildings and other civilian sites during the early weeks of the war may have violated international humanitarian law.
The Israeli prime minister’s office and foreign ministry did not immediately respond to a request for comment.
Meanwhile, the Israeli regime’s military assault on Gaza has generated around 61 million tons of wreckage and debris that the United Nations says could take seven years to clear.
A US-brokered ceasefire ended full-scale fighting in October 2025 but has failed to stop regular Israeli strikes.
The Palestinian Civil Defence says more than 630 bodies and human remains have been recovered from beneath destroyed buildings across Gaza since November 2025.
Palestinian authorities estimate that more than 8,000 people remain buried beneath the wreckage.
Turk warned that the remains recovered so far could be “only the tip of the iceberg,” noting that large areas of Gaza had been flattened by Israeli bombing or subsequently demolished and cleared.
He also accused the Israeli regime of continuing to level areas of Gaza where its forces remain deployed, saying bulldozers were operating “with no respect for the dead under the rubble”.
Ajith Sunghay, head of the UN rights office for the Occupied Palestinian Territory, said Israeli restrictions on items including DNA kits and excavators were obstructing efforts to recover and identify the remains.
“The collective impact of Israel’s conduct is making any systematic, large-scale search, recovery, and identification work nearly impossible,” he told a Geneva press briefing.
He added that Palestinian teams were sometimes forced to dig through rubble with their bare hands.
More than 73,000 Palestinians have been killed in the Israeli regime’s military campaign, according to Gaza health authorities.
Turk called for international investigators to be granted access to all parts of Gaza to help preserve evidence, citing ongoing legal proceedings examining conduct during the war.
Francesca Albanese, the UN expert on the Palestinian territories, has said evidence should be gathered and human remains identified before full clearance operations begin.