On a patch of sandy ground between collapsed masonry, burnt out buildings and damaged cars, civil defence workers move from body to body, wrapping white shrouds around a group of people killed in Gaza's 11-week-old war.

As Israel fights to wrest full control of northern Gaza from Hamas militants, the scene in the Jabalia refugee camp reflects the deadly risk posed to Palestinians by relentless air strikes and shelling.

The activity was captured in a video released by the Palestinian Civil Defence service, which also showed a worker digging by hand to try to recover an apparently burned corpse trapped under rubble.

The Palestinian death toll in the conflict has reached 20,258, the Palestinian health ministry said on Saturday, with thousands more bodies believed trapped under rubble.

Almost all of Gaza's 2.3 million people have been displaced in one of the world's most densely populated areas.

Israel says it has achieved almost complete operational control over northern Gaza and is preparing to expand a ground offensive to other areas, but Jabalia residents reported persistent aerial bombardment and shelling from Israeli tanks, which they said had moved further into the town on Saturday.

Israel said on Sunday 154 of its soldiers have been killed since it launched its ground incursion in response to Hamas' Oct 7 rampage into Israel, in which militants killed 1,200 and took 240 hostages.

Palestinians of Khan Younis in the south were seen searching among the rubble for their belongings following a recent airstrike.

Standing amid debris, Khan Younis resident Sami Barees said his house had been destroyed, and the airstrike had taken place in what was supposed to be a safe zone.

"This is the security and safety that Israel claims," he said.

U.S. officials have said they want and expect Israel soon to shift its military operations in Gaza to a lower-intensity phase during which there will be more targeted operations focused on the Hamas leadership and its infrastructure.