The military says the rocket landed early Thursday in an open area near the city of Ashkelon. It says Israeli warplanes retaliated by targeting a "terror infrastructure" in the Palestinian territory.
Palestinian media in Gaza reported two Israeli airstrikes, in the north and central Gaza Strip. One targeted a watchtower near the Gaza-Israel border and the other a militant training site.
There was no immediate claim of responsibility for the rocket fire. Islamic militants in Gaza have claimed responsibility for sporadic rocket fire into Israel in recent months.
During last summer's war between Israel and the Hamas group in Gaza, more than 2,200 Palestinians, and 73 people on the Israeli side, were killed. The war disrupted the lives of millions of people as they coped with rocket attacks and air-raid sirens.
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