An Israel Air Force air strike against a Hamas police position in the southern Gaza Strip killed one person and injured three others early Saturday, Palestinian officials and the Israel Defense Forces said.

Hamas said one of its men was killed in the attack near the former settlement of Morag in southern Gaza. Channel 10 reported the three injured were all Hamas men as well.

The IDF said it struck a Hamas position following repeated rocket and mortar fire from Gaza toward towns in southern Israel.

Hamas police were seen taking precautions on Saturday after the IAF strike, with many leaving their posts, working from makeshift locations and with a smaller visible presence on the streets.

Ehab al-Ghussen, a spokesman for the Hamas-run Interior Ministry, however, said the police would not be deterred by the air strike.

"There is a serious escalation by the occupation against the Palestinian security establishment in Gaza," he said. "These threats are not going to block our efforts to achieve our goals. We have alternative plans, and we are working to protect our personnel and our establishment." He did not elaborate what kind of measures Hamas may take.

Four mortars were launched Friday at the western Negev, one of which struck a local kibbutz, a day after Palestinian militants fired a barrage of nine Qassam rockets at the western Negev.

One of the rockets struck front yard of a home in the western Negev town and did not explode. Two other rockets landed in open fields - one outside Sderot and another near Kibbutz Nir Am. There were no injuries or damage reported.

In response, the Israel Air Force targeted two Qassam rocket launchers in the northern Gaza Strip, Army Radio reported.

Rockets have landed in the region on a daily basis, yet Sderot's chief security officer, Yehuda Ben Mamen, said the latest barrage prompted school principals to call and inquire as to whether classes would be in session. Ben Mamen replied that schools would be opened as per usual.