Prime Minister Benjamin Netanyahu on Wednesday night announced the onset of a broad aerial and naval bombardment of Hamas targets in the Gaza Strip, and said the country’s military was ready to widen its operations until its objectives were reached.

Netanyahu’s national security cabinet also announced it had tasked the Israel Defense Forces with calling up extra reserve units, should the need arise, a possible precursor to a wider ground operation.

The announcements came hours after an Israeli Air Force strike killed Hamas military chief Ahmed Jabari, the first blow in the army’s Operation Pillar of Defense in Gaza.

“Today we sent a clear message to the Hamas organization and to other terrorist organizations, and should the need arise, the IDF is prepared to broaden the operation,” Netanyahu said at a joint press conference with Defense Minster Ehud Barak. “We will continue to do everything to protect our citizens.”

He blamed Hamas for escalating its attacks against civilians, and added that Israel was “not prepared to make peace with a situation in which Israel’s citizens are menaced by the terror of rocket fire.

“No country would agree to such a situation; Israel is not prepared to reconcile itself to such a situation.”

The Israeli military said it was ready, if necessary, to send ground troops into Gaza. The defense officials who said a ground operation was likely in the coming days spoke on condition of anonymity because they were discussing sensitive military plans.

The prime minister reiterated the IDF’s report that Israeli Air Force planes had “damaged strategic targets of Hamas in a precise fashion” and “substantially damaged the launch capabilities of rockets from Gaza” at central and southern Israel.

“The terror organizations hurt our citizens with premeditation, while they deliberately conceal themselves behind their own citizens,” he said.

Speaking after Netanyahu, Barak told reporters that “the accuracy of the Shin Bet’s information and the sharpness of the IDF’s operation brought about the assassination of Hamas chief of staff [Ahmed] Jabari and the neutralization of Fajr missiles and Hamas’s infrastructures.” He added that most of Hamas’s Fajr long-range rocket arsenal was destroyed in IAF airstrikes.

Barak noted that Operation Pillar of Defense would not be completed in “one fell swoop,” but that the objectives would be attained in due time.

The defense minister delineated the operation’s objectives as “strengthening deterrence, damaging the rocket arsenal, damaging and hurting Hamas and minimizing injury to the civilians on the homefront of the State of Israel.”

“The IDF will receive all of the support to do everything necessary in order to return calm to the South,” Barak said.

Smoke billows over Gaza after a series of IAF airstrikes that marked the onset of Operation Pillar of Defense, Wednesday, November 14, 2012 (photo credit: Edi Israel/Flash90)

Smoke billows over Gaza after a series of IAF airstrikes that marked the onset of Operation Pillar of Defense, Wednesday, November 14, 2012 (photo credit: Edi Israel/Flash90)

In an earlier address to the press, former deputy chief of General Staff Maj. Gen. (res.) Dan Harel said that “Hamas thought [Israel] would not retaliate” to rocket barrages in recent weeks. “They were wrong.”

Hamas has escalated its smuggling of high-quality weaponry recently, Harel explained, and “felt it has enough power to face down Israel,” Harel said. “We are in the early hours of the clash, and where it goes from here depends on Hamas’s activity.”

Besides the killing of Jabari, he added, “some of the long-range rockets of Hamas were destroyed. Fighter jets are bombing rocket cylinders buried in the ground. We’re trying to take away [Hamas’] launching capability. It will be difficult, but we’re doing our best.”

Israel does not wish to launch a ground operation, Harel said, but is willing to do so to stop the rocket fire.

“We’re not looking at going further on the ground, but if we have to do it, we will do it.”

Haviv Rettig Gur and the Associated Press contributed to this report.