Sunday's deaths brought the toll to 357 Palestinians, and seven Israelis, including two civilians, who have died since the operation began on July 8.
Heavy artillery shelling east of Gaza City early in the morning killed at least six people, emergency spokesman Ashraf al-Qudra said.
In one artillery hit in Shejaiya east of Gaza City, a woman, two children and the son of senior Hamas official Khalil al-Hayya were killed, Qudra told AFP.
Earlier, tank fire killed 56-year-old Hosni al-Absi in the southern city of Rafah.
An air strike in Rafah killed three young men, all brothers, and wounded 10 more people, Qudra said. Hours later, another strike in Rafah killed three people.
Shortly after that, a strike in the central Strip killed a 29-year-old man.
During Israel's operation to stamp out rocket fire from the besieged territory, some 1,333 rockets have hit Israel, with 360 intercepted by its Iron Dome defence system.
Israel's military has hit thousands of targets in the besieged coastal territory.
Five Israeli soldiers have been killed since the operation was launched on July 8, the army said.
Two Israeli civilians, including a Bedouin man, have died in cross-border fire.
Nearly 2,400 Palestinians have been wounded in the biggest confrontation in and around Gaza since Operation Cast Lead, a bloody 22-day offensive which ended in January 2009.
Gaza's health ministry said in a statement early Sunday that the Israeli artillery attack on Shejaiya had targeted ambulances trying to evacuate the wounded.