Not long after Israel resumed its offensive in Gaza on Sunday, Hamas said it agreed to a 24-hour U.N.-mediated cease-fire.
Just hours earlier, the heavy thump of Israeli artillery echoed once again across parts of the territory, and black plumes of smoke rose from eastern neighborhoods of Gaza City.
"Following Hamas' incessant rocket fire throughout the humanitarian window, which was agreed upon for the welfare of the civilian population in Gaza, the IDF will now resume its aerial, naval and ground activity in the Gaza Strip," the Israeli Defense Forces said in a statement.
The Israeli Security Cabinet had agreed to a U.N. request late Saturday to extend a cease-fire that started Saturday morning until midnight Sunday (5 p.m. ET Sunday) -- on the condition that its military could keep dismantling and destroying Hamas' tunnels, according to senior Israeli officials.
Hamas rejected that idea, saying it won't tolerate Israeli troops in the territory. And militants in Gaza fired mortars and rockets into Israel late Saturday and through Sunday morning, killing an Israeli soldier, the IDF said.
But the militant group that is in control of the besieged Palestinian territory soon changed its stance.
The group agreed to a 24-hour U.N.-mediated "humanitarian pause" starting at 2 p.m. local time (7 a.m. ET), a text message from Hamas spokesman Sami Abu Zuhri said.
"In response to the intervention by the United Nations and taking into account the conditions of our people and the upcoming Eid holiday, an accordance has been reached between Palestinian resistance groups to call a humanitarian calm for 24 hours," Zuhri said.
Israel launched its ground incursion in Gaza 10 days ago with the stated aim of taking out the threat posed by the tunnels, which run under the border and have been used by militants to carry out attacks on Israeli soil.
The temporary truce in the conflict -- which has killed more than 1,000 people, most of them Palestinian civilians -- had enabled medical supplies to be brought into Gaza, families to emerge from shelters and people to dig out the dead from piles of rubble.
'I'm very, very worried'
Hamas said it wasn't willing to prolong the calm under the current circumstances.
"Any humanitarian cease-fire that does not include the withdrawal of the occupation soldiers from Gaza borders and allowing citizens to return to their homes and evacuate casualties is unacceptable," Hamas spokesman Sami Abu Zuhri said.
Militants in Gaza had already resumed firing rockets and mortars into Israel on Saturday evening. The original 12-hour cease-fire had begun at 8 a.m. Saturday (1 a.m. ET).
"Yet again Hamas is cynically exploiting the residents of Gaza in order to use them as human shields," a media adviser for Israeli Prime Minister Benjamin Netanyahu said in a statement, pointing out that Hamas had rejected or breached several previous cease-fires since the fighting began.
Palestinian officials have repeatedly expressed concern about the lengthening conflict in Gaza.
"I'm very, very worried," said Saeb Erakat, a senior official in the Palestine Liberation Organization. "We are witnessing the gradual reoccupation of Gaza."
IDF spokesman Lt. Col Peter Lerner told CNN on Sunday that Israeli forces believe they are "about halfway through" their effort to get rid of the militant tunnels.
Death toll over 1,000
The IDF said Saturday that 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.
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.
Nearly 1,050 Palestinians have been killed and about 6,000 wounded since the Israeli operation against Hamas in Gaza started on July 8, al-Qedra said.
The Israeli operation started with airstrikes, and a ground incursion in Gaza followed on July 17.
Israel blamed Hamas for civilian casualties resulting from Israeli strikes.
"The IDF targets terrorist centers, but if residents are inadvertently hit, it is Hamas which is responsible given that it has -- again -- violated the humanitarian truce that Israel acceded to," Netanyahu's media adviser said.
The IDF said Sunday that the soldier killed overnight brought to 43 the number of Israeli troops killed in the Gaza operation. Two Israeli civilians have been killed.
U.S. Secretary of State John Kerry and other diplomats pushed for an extended truce In Paris on Saturday. Kerry met with Turkish Foreign Minister Ahmet Davutoglu.
Kerry had spent most of last week meeting officials in the Middle East to try to broker a more lasting end to the fighting. But so far, his efforts have born little fruit. He returned to the United States early Sunday.
"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 Saturday in a statement, reiterating his call for seven-day humanitarian cease-fire.
But Hamas officials reiterated their calls for a broader set of terms to be part of any truce.
"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 -- referring to Israel's longstanding restrictions on the movements of people and goods in and out of Gaza.
She accused Israel of "escalating the situation" in the so-called buffer zone and of not letting medical workers remove bodies in certain areas.
'Nothing is left'
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 that had been reduced to rubble by the fighting.
"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 met a neighbor as she navigated her way through mounds of rubble and metal. "Did you see my home?"
"It's gone. Nothing is left," the neighbor responded.
Families across the small, impoverished territory took advantage of the cease-fire Saturday to stock up on provisions.
"There are more people in the streets," said a mother of five in the Khan Younis area of southern Gaza, 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."
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