Israeli aircraft carried out attacks in the Hamas-controlled Gaza Strip early Sunday, Palestinian security officials said, hours after militants in the enclave launched three rockets at the Jewish state.

The strikes targeted two sites belonging to Al-Qassam Brigades, the Hamas military wing, in northern Gaza, with another series of sorties at a Qassam site west of Gaza City, Hamas officials said.

All three projectiles were intercepted by the Iron Dome defence system, the army said, amending an earlier statement according to which two of the three rockets were shot down over southern Israel.

Medics had treated three people in the southern Israeli town of Sderot who suffered minor injuries while seeking shelter as air raid sirens went off, the Magen David Adom emergency medical service said.

Hamas has controlled Gaza since 2007, and Israel holds the Islamist movement responsible for all rocket fire coming from the territory, although it has targeted other militant groups there.

Last month, Israeli forces assassinated a senior Islamic Jihad leader in the Gaza Strip, sparking a two-day flare-up which killed 36 Palestinians.