Israel renewed its bombardment of Gaza in the early hours of Wednesday morning, hitting the homes of several Hamas leaders.
Three people were killed – two suspected Islamists died after their car was hit.
Several others, mainly civilians, were injured in the latest air strikes.
It followed a warning by Israel that it will intensify its raids after the rejection of a truce by Hamas.
Thousands of supporters of the Gaza militants have demonstrated in the West Bank town of Hebron.
Hamas says it will not end its rocket fire into Israel without a political settlement.
Israel launched Operation Protective Edge nine days ago to halt the militants’ rockets but so far over 190 Palestinian civilians have been killed according to Gaza officials.
On Tuesday the first Israeli casualty was reported.
Israel has now ordered 100,000 Palestinians in eastern and northern Gaza to leave their homes indicating a possible limited ground offensive.