Planes and tanks have pounded parts of Gaza City as Israel's plans to seize the territory's largest urban area increase pressure on nearly a million Palestinians living there.
Residents have spoken of uninterrupted explosions in northern and eastern parts of the city.
Israeli troops have also returned to blow up buildings in the refugee camp of Jabalia further north.
Sixty-four people were killed and nearly 300 injured in Israeli attacks in the past 24 hours, the territory's Hamas-run health ministry said.
It said the overall number of those killed since Israel launched its massive campaign to defeat Hamas had risen to 62,686 - with another 157,951 injured.
