Israel launched its offensive on July 8 to halt missile salvoes by Hamas Islamists, who were struggling under the weight of an Israeli-Egyptian economic blockade and angered by a crackdown on their supporters in the nearby occupied West Bank.
After failing to halt the militant barrage through days of aerial bombardment, Israel sent ground troops into Gaza last Thursday, looking to knock out Hamas's missile stores and destroy a vast, underground network of tunnels.
Some 643 Palestinians, many of them children and civilians have died in the conflagration, including a seven-year-old hit by a shell in southern Gaza early Wednesday, a medic said.
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Some 29 Israeli soldiers have been killed, including a tank officer shot by a Palestinian sniper overnight. Two civilians have been slain by rocket fire. The military says one of its soldiers is also missing and believes he might be dead. Hamas says it has captured him, but has not released his picture.
Clouds of black smoke hung over the densely populated Mediterranean enclave, with the regular thud of artillery and tank shells filling the air.
"We are meeting resistance around the tunnels ... they are constantly trying to attack us around and in the tunnels. That is the trend," said Israeli military spokesman Lieutenant-Colonel Peter Lerner.
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He said 30 militant gunman had been killed overnight, bringing the total to 210 since the offensive started.
Hamas's armed wing, the Izz el-Deen Al-Qassam, said its fighters had detonated an anti-personnel bomb as an Israeli army patrol passed, killing several troops. There was no immediate confirmation from Israel.
There was also violence in the occupied West Bank, where a Palestinian was shot dead by Israeli troops near Bethlehem. The army said soldiers fired a rubber bullet at him during clashes with Palestinians hurling rocks and Molotov cocktails.
The Palestinian decision-making body led by U.S.-backed Abbas on Wednesday endorsed demands by Hamas for halting Gaza hostilities with Israel, a closing of ranks that may help Egyptian-mediated truce efforts.
Egypt has tried to get both sides to hold fire and then negotiate terms for protracted calm in Gaza, which has been rocked by regular bouts of violence since Israel unilaterally pulled out of the territory in 2005.
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Hamas, which refuses to recognise Israel's right to exist, has baulked at Cairo's offer, saying it wanted assurances of relief from an Israeli-Egyptian blockade and other concessions. The dispute was further complicated by distrust between Egypt under President Abdel Fattah al-Sisi and Hamas.
In a move that could effectively turn Abbas into the main Palestinian point person for a Gaza truce, his umbrella Palestine Liberation Organization (PLO) on Wednesday formally supported core conditions set by the Hamas-led fighters.
Egyptian sources said a unified Palestinian position could help achieve a deal. Unlike Hamas, the PLO has pursued peacemaking for two decades.
Israel faced mounting international alarm at the civilian death toll, as well as increased economic pressure from lost tourism revenues after the U.S. Federal Aviation Administration (FAA) took the rare step on Tuesday of banning