Fierce fighting between Israeli troops and Hamas militants continued near Gaza City on Monday as the death toll from the conflict rose above 500.
Heavy bombardment hit areas east of the city, particularly the neighborhood of Shaja'ia, where a large Israeli assault Sunday contributed to the deadliest day of the war so far.
As clashes escalated over the weekend, Hamas said it had captured an Israeli soldier - a claim Israel later denied.
With no sign of either side backing down in a conflict in which most of the victims have been civilians, U.S. Secretary of State John Kerry is due to arrive in Egypt on Monday to push for a cease-fire.
Speaking to CNN's "State of the Union" on Sunday Kerry said that the United States supports Egypt's initiative for a truce and "will work for a fair cease-fire."
The United States has "shown our willingness to try to deal with the underlying issues," but Hamas "must step up and show a level of reasonableness," he said.
"No country, no human being, is comfortable with children being killed, with people being killed, but we're not comfortable with Israeli soldiers being killed either or with people being rocketed in Israel," Kerry said.
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