Ahmed Jabari, head of the military wing of Hamas, was killed Wednesday in an air strike in Gaza by the Israeli Air Force, CBN News reports. Three others, including his son, were reportedly killed. Jabari, a senior commander with the Izz al-Din al-Qassam Brigades, helped plan the June 2006 kidnapping of former IDF soldier Gilad Shalit and had vowed to abduct more soldiers to use for bargaining in prisoner swaps. Jabari was in charge of coordinating relations between Hamas, al Qaeda and Islamic Jihad and was also behind the rocket attacks that began last weekend. IDF Maj. Gen. (ret.) Israel Ziv, former head of IDF operations, said the operation that began Wednesday, called Operation Pillar of Defense, sends a "very clear message to Hamas" that Israel is unwilling to continue with a situation that has taken so many Israeli citizens hostage. "I'm sure it's a big shock to the Hamas to get such a hit," Ziv said. "Definitely for them it's a kind of declaration of war." An IDF spokesman said the operation was rapidly escalating and the Israeli Air Force targeted 20 missile storage sites throughout Gaza. Hamas confirmed the news on its satellite TV channel, vowing to retaliate in "calculated attacks" and warning Israeli Prime Minister Benjamin Netanyahu he would regret the operation.