(JERUSALEM) -- Israeli air strikes on the Gaza Strip stretched into another day as Hamas and other militant groups retaliated -- the latest escalation of violence between the two sides that followed Israel's assassination Wednesday of Hamas' top military commander.
Three Israelis were killed in the southern town of Kiryat Malakhi by rocket fire Thursday morning. These are the first Israeli deaths in this escalation.
Israel's Air Force has hit more than 150 targets across Gaza since the operation -- dubbed "Pillar of Defense" -- began Wednesday evening. The first strike was on Ahmed Jabari, the chief of staff of the military wing of Hamas, the Ezzedeen al-Qassam Brigades. It was followed by a wave of air strikes on other militants, buildings and installations, notably launching sites and rockets, which included the long-range Fajar rockets that could reach Tel Aviv.
Hamas, Islamic Jihad and other militant groups have retaliated with almost 200 rockets fired into southern Israel, according to Israel's military. At least three Israelis were killed in the southern town of Kiryat Malakhi when a rocket hit an apartment building.
Hamas sources said a dozen Palestinians have been killed, including at least two children.
"We are still at the beginning of the event, not at the end, and we expect some complicated tests ahead," Israeli Defense Minister Ehud Barak said in a nationally televised address Monday night, standing next to Prime Minister Benjamin Netanyahu.
Israel has warned that it is ready to enlarge the operation with a ground operation, and reservists have been called up.
Israeli officials say the operation is in response to more than 800 rockets that have landed in Israel this year. Barak laid out the four goals of "Pillar of Defense": to strengthen deterrence, damage the rocket launching network, hit Hamas and its allies, and to minimize the damage in Israel.
"We recommend that no Hamas operatives, whether low level or senior leaders, show their faces above ground in the days ahead," the Israel Defense Forces tweeted Monday night.
Hamas warned that Israel will pay a heavy price for Jabari's assassination, with its armed wing saying Israel had "opened the gates of hell."
Hamas announced Thursday morning that Jabari's deputy, Marwan Issa, would take Jabari's place as de facto commander.
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