Two children were killed by an Israeli missile that hit a tent encampment Gaza's al-Mawasi, as Israeli strikes across the enclave killed at least 15 people on Sunday, medics told Reuters.
The children's mother and a sibling were also injured in the attack, according to medics at the Nasser Hospital.
Four people were killed in a separate strike in Rafah, near the border with Egypt.
In the central Gaza camp of Nuseirat, an Israeli airstrike killed six people in a house, and another attack killed three in a home in Gaza City, according to medics.
Israeli forces kept up bombardments across the enclave and blew up houses on its northern edge.
Residents said the military blew up clusters of houses in the northern Gaza areas of Jabalia, Beit Lahiya and Beit Hanoun, where Israeli forces have operated since October this year.
Meanwhile, a Saturday raid on the Jabalia refugee camp in northern Gaza killed a further 40 people, pushing up the total death toll to at least 100.