An Israeli Merkava tank near the Hamas-controlled Gaza Strip border in southern Israel, on Thursday. The Pentagon confirms that Israel tapped a U.S. weapons stockpile for tank rounds. Debbie Hill/UPI/Landov hide caption

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An Israeli army officer walks near the entrance of a tunnel allegedly used by Palestinian militants for cross-border attacks, at the Israel-Gaza border. A network of tunnels Palestinian militants have dug from Gaza to Israel is taking center stage in the latest war between Hamas and Israel. Jack Guez/AP hide caption

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A Palestinian girl cries while receiving treatment Wednesday at a hospital in Beit Lahiya for her injuries caused by a strike at a U.N. school in the Jebaliya refugee camp. Khalil Hamra/AP hide caption

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Palestinian Saeb Afana, 12, stands on the edge of a large crater from an Israeli missile strike that destroyed several graves, as he carries flowers at a cemetery in Gaza City on Monday. Lefteris Pitarakis/AP hide caption

itoggle caption Lefteris Pitarakis/AP

During Saturday's humanitarian cease-fire, families returned to the Shejaiya district of Gaza City Saturday to find their homes ground into rubble by Israeli tank fire and air strikes. An attempt to extend the cease-fire by an additional 24 hours ended early Sunday, but Hamas said it would accept a new cease-fire, partly to acknowledge the holiday of Eid. Mahumud Hams/AFP/Getty Images hide caption

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An Israeli army officer on Friday shows journalists a Palestinian tunnel that runs from the Gaza Strip into Israel. Israel says its current military campaign is aimed at destroying the tunnels. Jack Guez/AFP/Getty Images hide caption

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A Palestinian man leans on his car after salvaging usable items from his destroyed house in Shuja'iyya neighborhood in east Gaza City, on Saturday. Gazans are taking advantage of a brief cease-fire with Israel. Oliver Weiken/EPA /Landov hide caption

itoggle caption Oliver Weiken/EPA /Landov

Israeli troops come out of the Gaza Strip on Friday following combat operations in the territory. Israel's military is the strongest in the Middle East, but has waged a series of protracted fights in recent years without winning clear-cut victories. Jack Guez/AFP/Getty Images hide caption

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Injured Palestinian children lie on the floor of an emergency room after the U.N. school where they took refuge in the northern Gaza Strip was shelled. Lefteris Pitarakis/AP hide caption

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