An airstrike late on Monday damaged two houses in the town of Beit Lahiya in northern Gaza, killing at least 20 people, the Palestinian official news agency WAFA and Hamas media said.
Ten were killed in central areas of the Palestinian enclave – six in separate airstrikes on Gaza City and the town of Deir Al-Balah, and four in the town of Al-Zawayda around midnight on Monday, medics and health officials said.
At least five others were killed in an Israeli strike on a house in Jabalia north of Gaza City, medics said later Tuesday.
Later Tuesday, Israeli planes dropped leaflets over Beit Lahiya ordering residents who have not yet left their homes and shelters housing displaced families to quit the town completely.
Palestinians said the new attacks and Israeli orders for people to evacuate were aimed at emptying areas to create buffer zones.
More than 43,300 Palestinians have been killed in more than a year of war in Gaza, and much of the territory has been reduced to ruins.
Announcing plans for a rare transfer of patients out of Gaza, a World Health Organization official said more than 100 people would be evacuated from Gaza Wednesday, including children suffering from trauma injuries and chronic diseases.
They will travel via the Kerem Shalom crossing with Israel before flying to the United Arab Emirates, said Rik Peeperkorn, WHO representative for the Occupied Palestinian Territory.
In the Israeli-occupied West Bank, the Palestinian health ministry said at least seven people were killed Tuesday during an Israeli military raid and airstrikes.