(CNN) -- Airstrikes following a rocket attack targeted Palestinian militants in Gaza early Tuesday, the Israeli military reported.
One of the strikes hit a group of militants preparing to fire more rockets into Israel, according to the military.
The strike killed one militant from Izzedine Al Qassam brigade, the Hamas military wing, and seriously wounded two others, Palestinian medical sources said. Hamas is the Palestinian faction that controls Gaza.
Three other Palestinians were lightly injured in strikes against training bases near Gaza City, Khan Younes and Rafah.
The Israeli retaliation followed a rocket attack on the southern Israeli city of Beer Sheva that caused minor damage. There was no immediate claim of responsibility for the attack.
Journalist Talal Abu Rahma contributed to this report