Israeli warplanes staged four attacks in Gaza overnight, injuring two Palestinian fighters, a Palestinian medical source and witnesses said early Tuesday.
The raids came after Palestinian militants fired nine mortar shells into southern Israel on Monday that fell on open ground and caused no casualties, the army said.
Three raids targeted the town of Khan Younes in the south of the territory controlled by Hamas, wounding two fighters -- one of them seriously, the sources said.
The other raid occurred in a northern town and did not cause any casualties or damage.
The Israeli military did not deny or confirm the reports.
Two mortar rounds were fired at Israel from Gaza on Sunday, hours after Israeli warplanes on Saturday night hit central Gaza, killing five militants as they were about to launch a rocket attack, according to the army and witnesses.
The raid was one of the deadliest since Israel's December 2008-January 2009 war on Gaza's Hamas rulers, codenamed Operation Cast Lead, which cost the lives of 1,400 Palestinians, mostly civilians, and 13 Israelis, 10 of them soldiers.
Since Operation Cast Lead, the number of rocket attacks has dropped considerably but the Israeli army says more than 200 rockets or shells have been fired this year.
