JERUSALEM (CBS News) -- Secretary of State John Kerry said Friday that he had not yet reached a deal between Israel and Hamas to call a seven-day humanitarian truce in the Gaza war but is continuing work.
Kerry's comments at a Friday evening press conference in Cairo closing days of shuttling between the Egyptian capital, Jerusalem and the West Bank trying to work out a week-long pause in fighting that has killed more than 820 Palestinians and 38 people in Israel.
Speaking alongside the U.N. secretary-general and the Egyptian foreign minister, Kerry insisted that there was a general agreement on the "concept" of a truce but that both sides had concerns over details of carrying it out. He said he was "confident" that the truce's fundamental framework would succeed.
"Gaps have been significantly narrowed," he said. "It can be achieved, if we work through some of the issues that are important for the parties."
In a statement issued shortly after Kerry spoke, Israel's defense minister announced Israel may soon broaden its ground operation in the Gaza Strip significantly. In a statement by Defense Minister Moshe Yaalon office, he is quoted as telling troops in the field that "you need to be ready for the possibility that very soon we will instruct the military to significantly broaden the ground operation in Gaza."
"Hamas is paying a very heavy price and will pay an even heavier price," Yaalon said. "At the end of the operation, Hamas will have to think very hard if it is worth it to taunt us in the future."
Gaza fighting continued alongside the truce efforts. Israeli airstrikes hit more than 80 sites in Gaza, while militants in the tiny Mediterranean strip fired 50 rockets at Israel, the army said. Among the sites hit in Gaza were 30 homes, including that of a leader of the Islamic Jihad group who was killed along with his sons, Palestinian officials said.
And unrest sparked by the conflict intensified in the West Bank, where five Palestinians were killed during protests against the Israeli operation in Gaza.
Thursday's deadly attack on a UN school in Gaza provoked outrage over night. At least 15 civilians trying to avoid the violence were killed. Barr...
Kerry's comments reflected the difficulty of reaching even a brief halt in fighting, with Israel determined to destroy Hamas military tunnels from Gaza and rocket fire. After U.N. chief Ban Ki-moon raised the possibility of a far less ambitious 12-hour cease-fire, Kerry said Israeli Prime Minister Benjamin Netanyahu had "expressed a willingness to discuss such a possibility."
Ban says, "The people of Gaza have bled enough."
The U.S. top diplomat said the goal of halting fighting for seven days was to provide time to work out further talks to address each side's demands. He said some "terminology" on a truce's framework still needed work.
Hamas demands the release of Palestinian prisoners in addition to an end to the 7-year-old border blockade imposed by Israel and Egypt after the group seized Gaza from the Western-backed government of Palestinian President Mahmoud Abbas.
Israeli TV reports said Israel's Security Cabinet unanimously rejected Kerry's proposal in its current form, mainly because it would mean Israel has to cut short the effort to destroy tunnels. But Kerry said he had not submitted a formal proposal to Israel for the Cabinet to vote on.
Israeli government officials were not immediately available for comment.
Israel considers the tunnels to be a strategic threat because Gaza militants have launched them for staging surprise attacks. Israeli troops have so far destroyed about half of the 31 underground passages discovered during the Gaza operation.
The worst round of cross-border fighting in more than five years has killed 828 Palestinians and wounded more than 5,200, according to Palestinian health officials. The U.N. says civilians make up three-fourths of the dead and a majority of the wounded.
In Israel, 38 people have been killed since July 8, including 35 soldiers, two Israeli civilians and a Thai worker.
The army announced on Friday that an Israeli soldier whom Hamas had claimed to have captured earlier this week had in fact died in battle on that day. The declaration lifts fears of a soldier in Hamas custody - one of Israel's worst-case scenarios in any fight with the militants.
The army said it determined that Sgt. Oron Shaul was killed among seven soldiers killed in a vehicle that was hit by an anti-tank missile in Gaza on Sunday. The others in the vehicle were confirmed dead soon after the battle ended but Shaul's remains were not immediately identified. Shaul is among the count of 35 soldiers killed in the fighting.
In Cairo, Kerry delayed his anticipated departure from Cairo for several hours to talk again by phone to Qatari officials who are serving as a go-between with Hamas, which the U.S. considers terrorist organization and cannot negotiate with directly.
As the Gaza fighting drags on, the West Bank is becoming increasingly restive.
Protests erupted Friday in the northern village of Hawara, near the city of Nablus, and the southern village of Beit Omar, near the city of Hebron. Palestinian hospital officials said three Palestinians were killed in Beit Omar and two in Hawara.
The mayor of Hawara, Mouin Idmeidi, said he and hundreds of others from the village participated in a protest after emerging from a local mosque after Friday prayers.
Hawara is located along a main north-south thoroughfare that is also used by Israeli motorists. The mayor said an Israeli motorist slowed down as he passed the march and fired at the group.
The mayor said four people were wounded and that one of them, a 19-year-old, died at Rafidiyeh Hospital in Nablus of his injuries.
After the shooting, clashes erupted between Palestinians and Israeli troops who opened fire, killing a 22-year-old from Hawara, the mayor said. Rafidiyeh hospital confirmed the deaths.
An Israeli police spokesman, Mickey Rosenfeld, said paramilitary border police opened fire to disperse violent protests at Hawara, and that masked Palestinians threw firebombs. He said he was unaware of a shooting involving an Israeli civilian.
In Beit Omar, clashes erupted between Israeli forces and Palestinian stone-throwers. Hebron hospital officials said three Palestinians were killed.
The Israeli military said it was looking into the reports.
On Thursday, thousands of Palestinians clashes with Israeli forces at a West Bank checkpoint and in east Jerusalem, the largest protests in those areas in several years.
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