A mural is seen on the remains of a house that witnesses said was destroyed by Israeli shelling during a 50-day war last summer in Beit Hanoun in the northern Gaza Strip. Suhaib Salem/Reuters /Landov hide caption

itoggle caption Suhaib Salem/Reuters /Landov

The Islamist group Hamas, shown here in a rally in the Gaza Strip on Dec. 12, is the strongest faction in the Gaza Strip. The Islamic State, or ISIS, is not believed to be in the territory, though fliers purporting to be from the group have circulated in Gaza. They are widely believed to be fake, but both Israel and Hamas have tried to use them to their advantage. Mahmud Hams/AFP/Getty Images hide caption

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A Palestinian with a green headband, which identifies him as a Hamas supporters, helps a fellow protester with a black-and-white scarf, the symbol of the Fatah movement. They were both taking part in a demonstration near the West Bank city of Ramallah on June 4. The factions agreed to end their feud earlier this year, but many of their supporters remain bitter rivals. Majdi Mohammed/AP hide caption

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A Palestinian worker checks a truck loaded with bags of cement as it crosses into southern Gaza from Israel last year. Israel has restricted cement supplies to only specific projects. Said Khatib/AFP/Getty Images hide caption

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Mai Hamada, 30, was injured by an Israeli airstrike on a home for the disabled in July in the Gaza Strip. Hamada has cerebral palsy and can't walk. Israel is investigating cases of possible illegal action by its military and may look into the attack on the group home. Emily Harris/NPR hide caption

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The destroyed and deserted main gate of the Gaza international airport in the southern city of Rafah. Thomas Coex/AFP/Getty Images hide caption

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Palestinians look out of a window frame in the northern Gaza Strip city of Beit Hanun on Monday. Media reports say a cease-fire has been extended for 24 hours. Thomas Coex/AFP/Getty Images hide caption

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An Israeli Merkava tank drives past a field of sunflowers along the border between Israel and the Gaza Strip as it moves out of the Gaza Strip on Aug. 3. Gil Cohen Magen /AFP/Getty Images hide caption

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Displaced Palestinian Emada Al Attar, 23, holds her 16 day-old baby boy Anous in a classroom where they sleep in a U.N. school where the family is taking refuge during the war, in Gaza City, Gaza Strip on Aug. 8. Lefteris Pitarakis/AP hide caption

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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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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

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

itoggle caption Lefteris Pitarakis/AP

A Palestinian carries a wounded girl in the emergency room of Shifa Hospital in Gaza City. The city's main hospital is filled with the wounded, and many others have taken refuge on the hospital grounds. Lefteris Pitarakis/AP hide caption

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A Hamas supporter holds her mobile phone during a public rally in Gaza City in March. Said Khatib/AFP/Getty Images hide caption

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