Bodies of Palestinians were discovered at the Khalifa Bin Zayed school in Beit Lahia which at one point sheltered thousands of displaced people

Dozens of Palestinians were found dead at a school in the northern Gaza Strip in black body bags tied with plastic cables bearing Hebrew writing.

The bodies of 50 Palestinians were discovered at the grounds of the Khalifa bin Zayed elementary school in Beit Lahia on Tuesday after Israeli forces withdrew from the area, local residents told Middle East Eye.

The bodies were discovered under a mound of rubble at the school with videos uploaded on social media sites showing several of the body bags tied with white plastic zip ties, normally used for tying cables together.

According to eyewitnesses assisting in identifying the deceased, Israeli forces reportedly executed the Palestinians nearly two months ago on a road near the school.

The school had served as a shelter for thousands of displaced Palestinians before it was bombed and besieged by Israeli forces in early December. The school had been supported by United Nations Relief and Works Agency, also known as Unrwa, since 2010.

Hossam Shabana, a photojournalist working in northern Gaza, said that some of the victims included families, such as Abu Srour Abu Salah, 52, and his wife. The remains of an unidentified child were also discovered at the site.

"The bodies were removed from graves created by citizens in the shelter center [school], and they were abused and searched [by Israeli forces]," Shabana said. "These bodies were reported to have been handcuffed and blindfolded.

"After the occupation exhumed the graves and subjected the bodies to abuse and searches, the Israeli army proceeded to cover the bodies with nylon [sheets of plastic and the body bags] and discard them into what appeared to be a mass grave.

"Following the army's withdrawal from the area, a municipal member used heavy machinery to clear the debris left by Israeli bombings. It was then that the residents noticed the presence of the bodies," Shabana added.

MEE reached out the Israeli army for comment but did not receive a response by time of publication.

The grizzly discovery comes a day after more than 100 Palestinian bodies that were exhumed and taken by Israeli forces from various areas in the Gaza Strip were returned for a mass burial in the southern city of Rafah. 

Some of the bodies were unidentified when they were reburied while others had heavily decomposed, the Palestinian news agency Wafa reported. 

Later on Tuesday, the head of Hamas's political bureau, Ismail Haniyeh, said his group was studying a proposal that would offer Palestinians in Gaza six weeks of respite from fighting in exchange for the release of Israelis held captive in Gaza as well as the release of Palestinian prisoners held in Israel.

Haniyeh, who is based in Qatar, said Hamas was open to any "serious" initiatives provided they led to a "comprehensive cessation" of hostilities and the complete withdrawal of Israeli forces from Gaza.

His comments came after officials from Qatar, Egypt and the US met Israeli intelligence chiefs in Paris this weekend to discuss the release of some 136 Israelis held captive in Gaza.

The New York Times reported on Sunday that Hamas would release elderly captives, along with women and children, in exchange for Palestinian prisoners during an initial period of six weeks.

If that was successful, there could be another two phases of swaps, with male Israeli soldiers eventually included.

US Secretary of State Antony Blinken said on Monday that he could not confirm the details of the proposal, but referred to it as "a strong one and a compelling one".

Ben Gvir lashes out at proposal

The Israeli prime minister's office called the talks "constructive", but noted that there were "significant gaps which the parties will continue to discuss".

For weeks, Prime Minister Benjamin Netanyahu and his far-right government have vowed to remain in Gaza until Hamas is eliminated.

Speaking from an illegal Israeli settlement in the occupied West Bank on Friday, Netanyahu said: "We will not compromise on anything less than total victory.

"That means eliminating Hamas, returning all of our hostages and ensuring that Gaza will no longer pose a threat to Israel," he added.

However, Hamas political bureau member Mohammad Nazzal told Al Jazeera on Tuesday that an agreement to release the Israeli captives could only be possible with a full Israeli withdrawal from Gaza.

"We told the mediators a permanent ceasefire is our goal, but we can do it in the second or third stages of an agreement. Without an Israeli withdrawal from Gaza, we can't accept this new proposal," Nazzal said.

Israel's far-right National Security Minister Itamar Ben Gvir threatened on Tuesday to bring down the government if a "reckless" deal was reached with Hamas.

"A reckless deal = the dismantlement of the government," the far-right minister said on X, formerly known as Twitter.

Israel's relentless military offensive on the besieged Gaza Strip, which was launched after the 7 October attacks, has killed at least 26,637 Palestinians, most of them women and children.