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Israeli forces on Tuesday surrounded Mahdi Al Shawa school in Beit Hanoun, in the northern Gaza Strip, and fired at displaced Palestinians sheltering inside.
Mahmoud Hamdan, 30, told The National: “The occupation started a large-scale military operation after midnight and the vehicles advanced towards Beit Hanoun while we and thousands of people were present inside the schools.”
He said there were about 3,000 Palestinians inside the school.
In the past two weeks, some people have returned to their homes in Beit Hanoun, he said. But many of those at the school are reluctant to leave the building for fear of being shot.
“The army completely surrounded the school last night and people were unable to leave except for a few," Mr Hamdan said on Tuesday. "I, along with some guys, managed to escape with difficulty and reached Jabalia camp.”
Mr Hamdan left his family at the school, because he was worried he might be arrested by Israeli forces. He has been unable to contact his family since.
“We are trying very hard to communicate with our families at the school but it is difficult to make calls to check on them and see how they are doing," he said.
Ahmad Shabat is among those inside the besieged school. Israeli forces are calling on men to leave but evacuating is too dangerous, he said.
“We are hearing the sound of clashes and people who are trying to escape are shot,” he told The National.
“We have been under attack for hours and no one is helping us. Israeli forces could break into the school any time and kill us.”
Palestinian media sources said Israeli forces were arresting men who were inside the school.
“The situation is so difficult," Mr Shabat said. "Children and women are afraid and we can’t calm them down."
On Tuesday, Israeli warplanes dropped leaflets west of Deir Al Balah and in Al Zawayda, in the central Gaza Strip, saying the area north of Wadi Gaza is considered a "dangerous combat zone”.
The leaflets said the Israeli army "continue fighting terrorist organisations. Any other information will be published to warn you to avoid returning north of Wadi Gaza, as it poses a risk to your safety, so refrain from going back north.”
Four civilians were killed and several were injured in an Israeli air strike early on Tuesday that hit two houses in the southern city of Rafah.
At least 10 bodies were recovered from a mass grave at Al Shifa Hospital in Gaza city on Monday, the enclave's health authorities said.
The bodies were buried outside the reception area of what was Gaza's largest hospital, said Dr Moatasem Salah, a member of the emergency operations centre in the enclave's Health Ministry.
This month, the Israeli army withdrew from Al Shifa after an intensive, two-week siege that left the medical complex in ruins.
The UN rights office on Tuesday said Israel was still imposing illegal restrictions on humanitarian relief for Gaza.
"Israel continues to impose unlawful restrictions on the entry and distribution of humanitarian assistance, and to carry out widespread destruction of civilian infrastructure," Ravina Shamdasani, spokeswoman for the UN human rights office, said at a press briefing in Geneva.
