At least five Palestinians were wounded Saturday in a series of Israeli airstrikes in the Gaza Strip, witnesses and security sources said.

The Israeli bombings came after Palestinian militants fired tens of mortar shells and home-made missiles from the Hamas- controlled territory towards Israel.

The Israeli airplanes hit two security sites belonging to Hamas government in eastern Gaza City this morning, wounding five, according to the witnesses.

Adham Abu Selmiya, a health emergency spokesman of the deposed Hamas government, said that a security officer was seriously injured and a civilian sustained moderate wounds.

Meanwhile, at least ten Israeli artillery shell landed on the abandoned airport in southeast Gaza Strip.

Hamas government and the armed wing of the Islamic movement evacuated all their security and military sites for fears of more Israeli attacks.

An Israeli army spokesman told Israel Radio that the Palestinian militants have fired 50 shells from Gaza, which landed in western Negev, adding that two Israelis were lightly injured and a house was slightly damaged.

Saturday's rocket attacks are the largest by Palestinian militants since the end of Israel's three-week military offensive in the winter of 2008.