Israeli jets bombed two sites in Gaza early on Wednesday, wounding one woman, after Palestinians fired three rockets into southern Israel, Israeli and Palestinian sources said.
The Israeli military said its aircraft "targeted two weapons manufacturing sites in the northern Gaza Strip."
"Direct hits were confirmed and secondary explosions were identified," the military said in a statement.
Palestinian medical sources said one woman was slightly hurt in an Israeli air strike east of Gaza City and was taken to the nearby Shifa hospital.
The Israeli military said on Tuesday night that three rockets were fired into southern Israel from Gaza. None of them caused any casualties but one caused minor damage to a home.
A fourth rocket was fired into Israel from Gaza several hours after the air strikes, around noon (0900 GMT), striking in the Eshkol area but causing no casualties or damage, a military spokeswoman said.
No groups in Gaza claimed responsibility for the rocket fire, which came after months of relative quiet in the area, with just two rockets fired into Israel from the coastal territory in the past two months.
In April, tensions rose after a rocket-propelled grenade fired from Gaza hit an Israeli school bus, killing a teenager.
Israel responded with a series of air strikes that killed at least 19 Palestinians in the deadliest violence since Israel's devastating 22-day assault on Gaza in 2008-2009.
The violence raised fears of another such assault, but on April 10 the Hamas rulers of the Gaza Strip declared a return to the truce that ended Israel's Operation Cast Lead in January 2009, and the calm has largely held since then.