A new wave of Israeli airstrikes battered areas of Gaza early Thursday, continuing the deadly onslaught aimed at stopping militant rocket fire into Israel.
The days-long aerial bombardment of Gaza has killed 76 Palestinians, including women and children, and injured more than 500 since it began Monday, Palestinian officials said.
Israeli Prime Minister Benjamin Netanyahu said the offensive would be expanded and continue "until the firing at our communities stops and quiet is restored."
But there was no sign that Hamas and other militant groups in Gaza were backing down as rockets continued to streak over the border into southern Israel. No Israelis have been killed so far in the rocket attacks.
Some Israeli officials have hinted at the possibility of a ground offensive in Gaza, although questions remain about the government's appetite for such a conflict.
Netanyahu didn't specify what the expansion of the current operation, which began Monday, would entail, but he said Israel's military "is prepared for all possibilities."
President Shimon Peres, whose role is largely ceremonial and is not involved in setting policy, said in an exclusive interview with CNN's Becky Anderson that he believed a ground offensive "may happen quite soon" unless Hamas stops firing rockets at Israel.
"We warned them. We asked them to stop it," Peres told Anderson. "We waited one day, two days, three days and they continued, and they spread their fire on more areas in Israel."
While Peres was speaking on his own and his position may not outline an official government policy, Israeli Intelligence Minister Yuval Steinitz earlier told CNN that a ground operation "might become necessary."
Palestinian Authority President Mahmoud Abbas, meanwhile, convened an emergency meeting of his cabinet on Wednesday to discuss the crisis.
"This war is not against Hamas or another political party but it is against the Palestinian people," he told the media afterward. "What do you call this crime? What is this crime known under international law? To kill entire families, is this collective punishment?
"This is called collective genocide."
A Hamas spokesman, Sami Abu Zuhri, said Israel's threat to launch a "stupid" ground offensive didn't scare anyone, and fighters from Hamas' military wing were ready to face off with Israel's "coward" soldiers in Gaza.
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