Late on Friday Reuters quoted Palestinian medics as saying at least 30 people were killed and many more wounded in Israeli strikes on Jabalia that hit several houses.
The Palestinian official news agency Wafa said at least 20 women and children were among those killed. There was no immediate Israeli comment.
Before the latest strikes the Hamas-run health ministry in Gaza said at least 39 Palestinians, many in Jabalia, had been killed by Israeli strikes across Gaza on Friday.
Residents told Reuters that Israeli tanks had reached the heart of Jabalia under cover of heavy air strikes and artillery fire, and said Israeli troops were destroying large numbers of homes every day.
Later on Friday residents reported that communications had been cut in Jabalia and two other towns in northern Gaza.
On Friday the head of the UN’s Office for Humanitarian Assistance (OCHA), Georgios Petropoulos told the BBC’s Newshour programme that families in Jabalia were enduring “atrocious conditions”.
“We can’t hit the alarm bell hard enough about how dire and dangerous the situation for civilians there is,” he said, speaking from Rafah in southern Gaza.
“Families that are in north Gaza, especially the ones that are in Jabalia camp surrounded by Israeli forces, are trying to survive in what can only be described as atrocious conditions under a very heavy bombardment.”
On Thursday the Israeli military said it had killed numerous fighters in close-quarters combat and dismantled military infrastructure.
Mr Petropoulos added he did not foresee getting aid into the north of Gaza becoming easier as a result of Sinwar’s death.
Very little aid has entered northern Gaza in October. Israel said it sent in about 30 lorries of supplies into northern Gaza on Friday including food, water, medical supplies and shelter equipment. But local health officials told Reuters that aid has not been reaching the worst-affected areas such as Jabalia.
“We don’t see a path to peace from where we are in Gaza,” he said. “I still see children dying on the floors of hospitals for the lack of hospital beds… and dialysis patients dying because there is no fuel allowed to get to hospitals.”
Israel has repeatedly denied it is preventing aid from entering Gaza. But the US has told Israel to boost humanitarian aid access in Gaza or risk having some US military assistance cut off.
On Friday an Israeli minister told the BBC that Israel had “blockaded” parts of northern Gaza, which include Jabalia.
Amichai Chikli told the BBC’s Newshour programme: “We’ve created a blockade with our forces. We allowed the civilian population to escape into the safe zone, and we prevented supplies to enter the blockade region, which was a very specific region where Hamas was trying to recover its administration and its military capabilities.”
He insisted this was “legal according to the international law”.
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