At least 81 Palestinians have been killed and more than 400 injured in Israeli strikes across Gaza in the 24 hours until midday on Saturday, the Hamas-run health ministry said.
In one incident, at least 11 people, including children, were killed after a strike near a stadium in Gaza City, Al-Shifa hospital staff and witnesses told news agencies. The stadium was being used to house displaced people, living in tents.
Footage verified by the BBC shows people digging through the sand with their bare hands and spades to find bodies.
The BBC has contacted the Israeli military for comment.
Meanwhile, US President Donald Trump said he was hopeful a ceasefire could be agreed in the next week.
Qatari mediators said they hoped US pressure could achieve a deal, following a truce between Israel and Iran that ended the 12-day conflict between the countries.
In March, a two-month ceasefire collapsed when Israel launched fresh strikes on Gaza. The ceasefire deal – which started on 19 January – was set up to have three stages, but did not make it past the first stage.
Stage two included establishing a permanent ceasefire, the return of remaining living hostages in Gaza in exchange for Palestinians imprisoned in Israel, and the complete withdrawal of Israeli forces from Gaza.
On Thursday, a senior Hamas official told the BBC mediators have intensified their efforts to broker a new ceasefire and hostage release deal in Gaza, but that negotiations with Israel remain stalled.
A rally was organised on Saturday evening in Tel Aviv calling for a deal to free the remaining Israeli hostages held by Hamas in Gaza. Organisers said “the time has come to end the fighting and bring everyone home in one phase”.
Meanwhile, Israeli attacks in Gaza continue. Friday evening’s strike near the Palestine Stadium in Gaza City killed at least 11 people, hospital staff and witnesses said.
One witness said they were sitting when they “suddenly heard a huge explosion” after a road was hit.
“This area was packed with tents – now the tents are under the sand. We spent hours digging with our bare hands,” Ahmed Qishawi told the Reuters news agency.
He said there are “no wanted people here, nor any terrorists as they [Israelis] claim… [there are] only civilian residents, children, who were targeted with no mercy,” he said.
The BBC has verified footage showing civilians and emergency services digging through the sandy ground with their hands and spades to find bodies.
Fourteen more people were reported killed, some of them children, in strikes on an apartment block and a tent in the al-Mawasi area.
The strike in al-Mawasi killed three children and their parents, who died while they were asleep, relatives told the Associated Press.
“What did these children do to them? What is their fault?” the children’s grandmother, Suad Abu Teima, told the news agency.
More people were reported killed on Saturday afternoon after an air strike on the Tuffah neighbourhood near Jaffa School, where hundreds of displaced Gazans were sheltering.
The strike killed at least eight people, including five children, the Palestinian health ministry said.
One witness Mohammed Haboub told Reuters that his nephews, father and the children of his neighbours were killed in the strike.
“We didn’t do anything to them, why do they harm us? Did we harm them? We are civilians,” he told the news agency.
The health ministry said ambulance and civil defence crews were facing difficulties in reaching a number of victims trapped under the rubble and on the roads, due to the impossibility of movement in some of the affected areas.
