Israel struck Hamas targets in the Gaza Strip on Saturday, after a barrage of over 50 mortars were fired into southern Israel earlier in the day.
The Israeli air strikes on Gaza wounded five Hamas security officers and a boy, Gaza medics said.
Two Israelis were wounded and a home was damaged by the mortars fired from Gaza earlier in the day. Saturday morning's bombardment was the heaviest one launched by Gaza militants for months.
Hamas which rules the Gaza Strip, claimed responsibility for firing 10 of Saturday's mortars, an unusual move after a long period in which it had let other smaller militant groups do its bidding.
"Targeting the enemy's posts was a response to the ongoing Zionist assaults, airstrikes and tanks shelling on the Gaza Strip. The latest was two days ago, where two of our mujahidin were killed," said Hamas' armed wing, the Al-Qassam Brigades.
An Israel Defense Forces spokesman said Israel was holding Hamas "solely responsible for the attacks".
Gaza residents reported hearing constant shelling along the enclave's border with Israel and the IDF spokesman said tanks assisted by aircraft were firing at militant targets in the coastal strip.
Last month, two grad rockets were fired at Be'er Sheva for the first time since the city was hit by rocket fire in the 2009 Gaza war.
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