Palestinian sources say Israeli forces killed 23 Palestinians in fighting across the Gaza Strip Wednesday, including at least 11 militants and several children.

Witnesses say the dead included at least six Hamas gunmen and one Islamic Jihad member. They were killed in pre-dawn battles after Israeli troops backed by tanks and bulldozers moved into northern Gaza.

Medics say an artillery shell struck a house in Gaza, killing a young girl and her infant sister. A 3-year-old girl died earlier Wednesday in a separate incident.

Israel says it aimed its airstrikes at militants.

More than 100 Palestinians have been killed in Israel's military offensive in Gaza. The offensive began after Palestinian militants abducted an Israeli soldier in a cross-border raid late last month.

Israeli forces have been trying to find the soldier and to stop militants from firing rockets into Israel. A rocket fired into Israel Wednesday injured one person.

In other news, Saudi Arabia's King Abdullah has granted $250 million in aid to the Palestinians. The king's pledge coincides with a larger donation of one billion dollars to help with the reconstruction of war-torn Lebanon.

Some information for this report was provided by AFP, AP and Reuters.