GAZA - Israeli airplanes attacked two military sites of Islamic Hamas movement in the Gaza Strip late Thursday, security sources said.

The attacks caused damage in the training sites but there have been no reports on casualties, the sources said.

One of the sites is located in eastern Gaza City and the other in the middle of the coastal enclave.

Cross-border violence has been high for two days as Palestinian militants fired rockets into Israel from the Hamas-controlled territory.

Militants fired a rocket into Israel Thursday, an Israeli army spokesperson said, putting the number of missiles that have been fired at Israel for the past 48 hours to seven.

No Palestinian groups have claimed responsibility for the rocket fire, which renewed three months after Hamas persuaded militant factions to halt attacks following a few days of cross- border violence that left 19 Palestinians dead.