Israel launched an aerial attack on a Hamas military base in central Gaza early on Tuesday, killing three militants of the radical Islamic movement, witnesses and hospital sources said.
The witnesses said an Israeli aircraft fired two missiles at the base west of the central Gaza town of Beir el-Ballah, killing one on the spot and critically wounding two.
The target was a tent training base of Hamas' armed wing, the al-Qassam Brigades, they said.
An Israeli army spokeswoman confirmed the strike, saying it was in response to the "incessant" rocket and mortar fire from Gaza at southern Israel.
She said militants from the Hamas-controlled strip launched at least 240 mortar shells and locally-produced Qassam and al-Quds rockets at Israel last month.
One of the shells injured four Israeli soldiers at an Israeli army base outside the central Gaza Strip on Sunday.
Official figures said at least 21 Hamas militants have been killed in Israeli air strikes and gun battles with Israeli soldiers in the Gaza Strip since early last week.