Israeli soldiers are reported to have killed three Palestinian men near the Jewish settlement of Netzarim in the south of the Gaza Strip.
The Israeli military said the men were killed after they had opened fire on an Israeli convoy.
Earlier, a Palestinian teenager was killed by a shell fired from an Israeli tank in Jabalya in the northern Gaza Strip.
At least 60 Israeli tanks and other armoured vehicles have taken control of a zone of territory in the area.
The move followed a raid on the Jabaliya refugee camp yesterday in which at least 11 Palestinians were killed.
Palestinian security sources told AFP that another eight Palestinians were wounded in clashes between youths and Israeli troops in the town of Jabalya.
Israel has maintained the latest incursion is part of its ongoing campaign against militants. The latest incursions follow a suicide bombing on Wednesday which killed 15 people.
Meanwhile, Palestinian President Yasser Arafat has asked Mahmoud Abbas - who has kept a back-channel open to Israeli leaders during the past 29 months of fighting - to be prime minister.
68-year-old Abbas, second in command of the PLO, did not immediately accept the offer and said he wanted more details on what powers the role would entail.
