A five-year-old Palestinian girl was the youngest casualty on Monday when an Israeli artillery shell landed in the north of the Gaza Strip.
The girl died when the shell landed on her house near the town of Beit Lahiya, three other people were wounded.
In another attack a 60-year-old woman and her grandson were left dead after a shell hit their donkey cart.
Three other Palestinians were killed in another attack on Beit Lahiya.
The attack came after six rockets were fired at the Israeli town of Siderot by Palestinian fighters.
Ismael Haniyeh, the Palestinan prime minister, urged the US "to restrain the Israeli aggression and stop it".
"All that we ask the American administration is to take a moral stance toward the Palestinian people, and the Palestinian suffering and to bear its responsibility as a superpower in this world," he told the Associated Press news agency.
His comments came as Israel continued its attacks in Gaza.
In another Israeli strike earlier in the day, one man was hurt when an Israeli air strike hit a house belonging to Muhammad al-Shaikh Dib, a member of Al-Quds Brigades, the armed wing of the Islamic Jihad movement.
An Israeli military source said the house in the Shatti refugee camp was attacked because it contained stocks of weapons and rockets.
The source also said that the army had ordered the residents of the house to leave, minutes before the strike.
Haniyeh's comments came as the US Secretary of State Condoleezza Rice travelled to the Middle East to discuss Israel's offensive in Lebanon.
Rice was scheduled to meet with the Palestinian president, Mahmoud Abbas. She will not be meeting with Haniyeh as the US considers Hamas to be a terrorist organisation.