GAZA (CNN) -- A tenuous cease-fire in Gaza appeared to be over Saturday, with militant rockets again hurtling toward Israel as diplomats pushed for a longer truce in a conflict that has killed more than 1,000 people -- mostly civilians.
Israel had agreed to extend a humanitarian 12-hour cease-fire for four hours Saturday, but Hamas spokesman Abu Zuhri said there would be no extension.
The cease-fire started at 8 a.m. Saturday (1 a.m. ET). The temporary truce enabled Palestinians to move medical supplies into Gaza, families to emerge from shelters and people to dig the dead from piles of rubble.
The prospect of an extension faded quickly as the Israel Defense Forces accused militants of exploiting the humanitarian window by firing at Israel for the second time, with three rockets hitting the Sha'ar HaNegev regional council. Earlier Saturday, moments after the cease-fire officially ended, another three mortars were fired from Gaza and hit Israel in the Eshkol regional council. No casualties or damage were reported.
At about 4 p.m. ET, IDF said four rockets had been fired in the last hour: two were intercepted above Ashkelon, one was intercepted above the Shfela region and another came down in the Hof Ashkelon regional council.
The IDF said many Gaza residents were returning to previously evacuated areas despite repeated warnings, placing themselves at risk. It said operations against the tunnel threat continued and defensive positions were being maintained.
Israeli government officials told CNN that the United Nations has asked for a 24-hour humanitarian cease-fire extension. As a first stage, the Cabinet approved four additional hours until midnight, giving the Israeli Cabinet time to convene and discuss the request.
"We owe to the people of both Israel and Gaza our renewed effort to consolidate this pause in fighting into a more sustainable ceasefire," U.N. Secretary General Ban Ki-moon said in statement, reiterating his call for seven-day humanitarian cease-fire.
Palestinians found more than 100 bodies in areas that have been too dangerous to enter in recent days because of Israeli bombardment, Dr. Ashraf al-Qedra from the Gaza Ministry of Health told CNN.
More than 1,000 Palestinians have been killed and over 5,840 wounded since the start of an Israeli operation, al-Qedra said.
The possibility of a longer truce seems to have passed, according to comments from the Hamas camp.
"There won't been any talks about extending the cease-fire as long as there aren't talks about breaking the siege," said Israa Al-Mudalal of the Gaza Ministry of Foreign Affairs.
She accused Israel of "escalating the situation" in the so-called buffer zone and of not letting medical workers remove bodies in certain areas.
"We can't stop the firing (of rockets) until we have a real solution to this problem," she said. "There will be no peace as long as the siege continues."
Two senior Hamas officials, Izzat Risheq and Jamal Nazal, told CNN that the truce negotiations were tense and difficult.
Cabinet minister Yaacov Peri told Israel's Channel 10, "I wasn't asked yet for my opinion, but if I am asked, I will say yes to extending the cease-fire by a few hours."
In Paris on Saturday, U.S. Secretary of State John Kerry and other diplomats pushed for an extended truce. He met with Turkish Foreign Minister Ahmet Davutoglu.
The passions of the conflict, meanwhile, echoed across the world.
About 40 protesters were arrested in Paris on Saturday when a banned pro-Palestinian demonstration turned violent, authorities said.
Police brandished shields as they faced off with protesters in a cloud of tear gas at Place de la République, a busy pedestrian square in central Paris. Angry protesters hurled glass shards and rocks at police, set a small fire and smashed a bus shelter.
'There is no Eid'
A CNN team visiting the hardest-hit areas in northern Gaza where many of the newly-discovered bodies were discovered saw entire blocks of buildings reduced to rubble.
"I wish this cease-fire had never happened," one man in Beit Hanoun told CNN, "And I would have never found out my home is destroyed."
Another woman in Beit Hanoun meets a neighbor as she navigates her way through mounds of rubble and metal. "Did you see my home?"
"It's gone. Nothing is left," the neighbor responds.
Families took advantage of the cease-fire to stock up on provisions.
"There are more people in the streets," said a mother of five in Khan Younis, who did not want to be named. "People who were afraid before, go out now out of necessity. People with sick kids go to the hospital today. Buy Pampers today. Buy food today. I went to get bread for my family today."
She added, "When my husband goes to the mosque to pray, I pray that he comes back. ... If someone killed a cat in America, people make a bigger deal about it than children dying in Gaza."
As the Muslim world prepared to celebrate the Eid holiday in two days, Gaza residents buried the dead.
"There is no Eid," the woman in Khan Younis said. "In the Gaza Strip,
it would be absurd for anyone to bake cookies."
Israel Defense Forces have accused militants of hiding weapons in shelters and schools and firing rockets at civilians. The IDF said it will keep working to "locate and neutralize tunnels" being used by militants during the cease-fire and will respond with force if militants target Israeli civilians or soldiers.
The Israeli military said four soldiers were killed since Friday night in Gaza, bringing the total number of soldiers killed to 40 since Operation Protective Edge started.
Doctor: 'We are preparing ourselves for death'
The bloodshed is pushing hospitals in Gaza to the limit. At South Gaza's European Hospital, the flood of bloodied children and adults has overwhelmed doctors.
"We sometimes work 20 hours continuous," Dr. Jamal Abu Hilal said.
Doctors here say they're sick of stitching up bodies mutilated by shrapnel.
"We feel exhausted. We feel anxious. We feel depressed," Hilal's colleague Dr. Shadi said.
In one room, surgeons worked on a child mangled by shrapnel. The rest of the boy's family was killed.
"Not even one square meter is safe in Gaza strip," Dr. Hassen al-Masri said.
He, too, is afraid of dying in the conflict. The doctor carries his identification papers with him all the time, even while treating patients -- just in case.
"We are preparing ourselves for death."
Casualties mount in West Bank
The violence has also expanded to the West Bank. At least four Palestinians were killed in outbreaks of violence in several parts of the West Bank, according to medical sources.
A 23-year-old man was shot near Huwara village outside Nablus by Jewish settlers, a doctor at the Rafidia Hospital said. The circumstances of his death are unclear, but it led to clashes between protesters and the Israeli military in which another man was killed, medical sources said.
Two more men were killed during clashes with Israeli troops at a checkpoint north of Hebron in Beir Ummar in the West Bank, according to Palestinian medical sources.
The violent protests came after the U.N. shelter in Gaza was hit, killing 16 people and wounding a couple hundred more -- most of them women and children.
Video from the school showed chaos amid pools of blood. There were so many victims than many gurneys included two wounded children.
The bloodshed left the U.N. Secretary-General Ban Ki-moon exasperated.
"I am telling to the parties -- both Israelis and Hamas, Palestinians -- that it is morally wrong to kill your own people," Ban said. The "whole world has been watching, is watching with great concern. You must stop fighting and enter into dialogue."
CNN's Karl Penhaul reported from Gaza; Ralph Ellis and Chelsea J. Carter wrote from Atlanta. CNN's Salma Abdelaziz, Yousuf Basil, Ben Wedeman, Elise Labott, Richard Roth, Ian Lee,Tal Heinrich, Holly Yan and Tim Lister contributed to this report.
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