The Israeli air force has fired missiles at the northern Gaza refugee camp of Jabaliya, Israeli military sources say.
Witnesses said two Palestinian civilians were hurt when the aircraft fired three missiles at the camp.
An Israeli military source said the strike targeted militants who were preparing a mortar attack.
Israel has scaled back its operations in Gaza and the West Bank under a ceasefire declared in February.
Israel is planning to evacuate all its 21 settlements in the Gaza Strip and the troops who protect them as part of a unilateral disengagement plan.
It will maintain control of the borders, airspace and coastline of Gaza, which is home to about 1.5m Palestinians.