Jerusalem (CNN) -- The Israeli air force struck three sites Friday in Gaza in response to rockets fired at communities in southern Israel, the Israel Defense Forces said.
Ten mortar rockets and a Grad rocket have been fired into Israel in the past two days, the military said. The mortar shells landed in open territory, but the Grad rocket hit near the city of Ofakim, causing some damage, said the military, commonly called the IDF.
Palestinian security sources said the strikes hit an Islamic Jihad base near Khan Yunes, a house in Deir El Balah, and an open space in Rafah. Four people were lightly wounded in the Deir El Balah strike, Palestinian medical sources said.
The military said in a news release that it "holds the Hamas terrorist organization solely responsible for maintaining the calm in the Gaza Strip and for any terrorist activity emanating from it."
"The IDF will also continue to respond harshly to any attempt to use terror against the state of Israel."
CNN's Michal Zippori contributed to this report.