Israeli airplanes struck a training site for Islamic Hamas movement in eastern Gaza City early Monday, apparently in response to rockets militates fired from the territory into Israel in the morning.

An Israeli Apache helicopter fired one missile towards the site that was empty at the time, witnesses said. There have been no reports of injuries, but the witnesses said fire broke out at the place.

Hamas, which controls Gaza, was expecting an Israeli military retaliation on the firing of three Grad rockets from the coastal enclave towards southern Israel on Sunday morning and evening. As a result, all Hamas security and military outposts were evacuated.

Israeli media reports said that at least three Israelis were slightly wounded when Gaza missiles landed in Western Negev and four were treated of shock.

Al-Qaeda-linked Salafist groups claimed reasonability for firing the rockets as they have done over the past days. The Salafists criticize Hamas for observing a shaky ceasefire with Israel and Hamas has been rounding up dozens of fighters affiliated with the Salafist groups.