A family, including six children, have been killed in the central Gaza Strip, in the latest waves of Israel’s deadly attacks across the besieged Palestinian territory.

At least 25 Palestinians were killed in the past 24 hours, the Gaza Health Ministry said on Sunday.

The parents and their six children were killed in Deir el-Balah in the central part of the Strip, Al-Aqsa Martyrs Hospital said. The grandfather of the children said their mother worked for the United Nations.

“My daughter, together with her husband and six children, was sleeping peacefully at home in Deir al-Balah. They were taken by surprise, an Israeli missile landed over their heads. The entire house was flattened. They were all killed,” Mohammed Awad Khattab told Al Jazeera.

“My daughter has been struggling to have children for years. She had those children through IVF … What wrong did those innocent children do? Were they posing any danger to Israel? Were they carrying arms?” he asked.

Al Jazeera’s Tareq Abu Azzoum, reporting from Deir el-Balah, said: “Four of her children were twins and they have been lined up together in order to be buried in cemeteries here in this town.

“We have seen really heartbreaking scenes this morning with dozens of bodies lined up in the morgue outside Al-Aqsa Hospital. There has been a remarkable surge in Israeli strikes in Deir el-Balah where Palestinians were told to seek refuge,” Abu Azzoum added

Israel’s 10-month-long offensive has so far killed more than 40,000 Palestinians in Gaza.

Elsewhere in the strip on Sunday, an Israeli aircraft bombed two apartment buildings in the Jabalia refugee camp, killing at least four Palestinians, the Wafa news agency reported.

Late on Saturday, an attack near the southern city of Khan Younis killed four people from the same family, including two women, according to Nasser Hospital.

And in the Nuseirat refugee camp in the centre of the Strip, seven people were killed, including three children, according to Al Jazeera Arabic.

‘Chaos and fear’

According to UNWRA, the UN agency for Palestinian refugees, areas designated as so-called “humanitarian zones” in Gaza by the Israeli military have shrunk to just 11 percent of the Strip, “causing chaos and fear among the displaced”.

Thousands of families continue to be displaced in #Gaza as Israeli authorities issue new evacuation orders. The so-called “humanitarian zone” has shrunk to just 11% of the #GazaStrip, causing chaos and fear among the displaced.

They have nowhere safe to go. #CeasefireNow pic.twitter.com/0VC7QhOuqe

— UNRWA (@UNRWA) August 17, 2024

Mohammed Moghayyar, the director of operations at Gaza Civil Defence, told Al Jazeera that Israel reducing the size of the humanitarian zone has cut off crucial facilities such as hospitals and increased the risk of diseases spreading.

“The more the Israeli occupation forces reduce the safe humanitarian zones, the more it continues to violate international law and the Geneva Convention, the more it causes death and killing among our people,” he said from Deir el-Balah.

Meanwhile, Hussam Abu Safia, the director of Kamal Adwan Hospital in Beit Lahiya in northern Gaza, has told Al Jazeera the medical facility will have to stop working within the next 24 hours due to a shortage of fuel and medical supplies.

On Sunday, the Israeli army said it is deepening its operations in Khan Younis and on the outskirts of Deir el-Balah.

Fighter jets attacked targets in Khan Younis from which rockets were launched towards the Nirim community in southern Israel yesterday, the army said.

Air attacks destroyed loaded launchers ready for attacks in the area, it added, saying that soldiers killed fighters and located weapons, including grenades, assault rifles and explosives.

Troops also kept operating in the Rafah area above and below ground, the army statement said.

As the war rages on, United States Secretary of State Antony Blinken headed to the region on Sunday for another attempt at procuring a ceasefire deal. In the Qatari capital, Doha, where Qatari, Egyptian and US negotiation mediators tried to hammer out a deal on Gaza, ceasefire talks were paused on Friday, but are expected to resume next week with the hope of concluding an agreement in Cairo.