At least 31 people died when a bomb destroyed a residential building in northern Gaza on Sunday, health care workers said.
A search was under way in the crowded Jabalia refugee camp for people trapped under the rubble of the multi-storey building.
The Hamas-controlled Health Ministry said the bodies of 45 people killed in Israeli air and artillery attacks had been brought to the al-Aqsa hospital in the central part of Gaza since Saturday evening.
The information could not be independently verified.
An Israeli mobile artillery unit fires a shell from southern Israel towards the Gaza Strip. (AP PHOTO)
The Israel Defense Forces (IDF) did not comment on the building's destruction and said its strikes targeted weapons depots, tunnel shafts and other Hamas-related sites.
The IDF said fighter jets, together with ground troops, destroyed a Hamas communications facility located next to a mosque in the south of the coastal strip.
Israeli Prime Minister Benjamin Netanyahu called on Hamas fighters to lay down their weapons, in a video broadcast on Sunday evening.
Netanyahu said "in recent days, dozens of Hamas terrorists" have surrendered to Israel's armed forces.
The war would continue, "but this is the beginning of the end for Hamas," he added. Recent IDF statements suggest Hamas has been weakened.
The Israeli military recently published videos from the north of the Gaza Strip showing groups of Palestinian men wearing only underwear, kneeing on the ground with eyes covered and hands tied behind their backs.
According to the IDF, these were scenes in which the men, who were said to be Hamas fighters, surrendered to Israeli soldiers.
However, their identities could not be independently verified, nor could the number of alleged surrenders.
The Haaretz newspaper wrote on Sunday, citing anonymous security sources, that of the several hundred Palestinians detained so far, only about 10 per cent to 15 per cent were affiliated with Hamas or other militant groups.
The war in the Gaza Strip was triggered by the largest massacre in Israel's history, carried out by terrorists from Hamas and other groups on October 7.
About 1200 people were killed. Another 240 were taken hostage, some of whom were released during a brief ceasefire.
In response to the October 7 attack, Israel launched massive airstrikes on the Gaza Strip, followed by a ground offensive that began in late October.
The Israeli military's bombing campaign has since killed more than 17,700 people in the Gaza Strip, according to the Hamas-controlled Health Ministry.
Palestinians mourn relatives killed in the Israeli bombardment of the Gaza Strip. (AP PHOTO)
Qatari diplomats said on Sunday they were still hoping to broker a ceasefire in the conflict.
Qatar and Egypt had brokered a now-expired truce that also led to the release of a number of hostages by Hamas.
The UN Office for the Coordination of Humanitarian Affairs (OCHA) said on Sunday the drinking water situation had improved slightly in southern Gaza, following pipe repair work and the installation of a mobile water tank.
But the UN warned there was still a severe lack of drinking water in the Gaza Strip, with residents resorting to drinking from unclean sources out of desperation.
According to the UN's World Health Organization, people in many parts of Gaza have access to less than two litres of water per day, well short of the minimum of seven litres per day needed for drinking, washing and cooking.
With many Gazans unable to wash themselves, diarrhoea and skin infections are spreading.
The UN agency for Palestinian refugees (UNRWA) says 85 per cent of Gaza's 2.2 million residents have had to flee their homes because they were damaged or destroyed, or because Israel had called for the evacuation due to military operations.
