Gaza: An Israeli air strike flattened the eight-story Palestinian Foreign Ministry building in Gaza City on Monday as part of a campaign against the Hamas militant group.

At least nine Palestinians were injured, most of them children. No deaths were reported.

The building, which was badly damaged in a previous attack, was completely destroyed, tearing through nearby homes, shops and offices.

"The explosion was so powerful that it knocked my children out of their beds, crying and screaming," said Umm Mohammed, who lives in an apartment across the street from the Foreign Ministry building.

Mohammed said the blast knocked out windows in the room where her children were sleeping. 

The Israeli army confirmed the air strike and accused Foreign Minister Mahmoud Al Zahar of Hamas of using his offices "to plan continued terror attacks against Israel".

Hamas, which came to power in the Palestinian territories after a January election, is dedicated to Israel's destruction.