GAZA CITY (CNN) -- The Israeli military launched a ground operation into Gaza late Thursday, the government said.
The much-anticipated operation follows some of the most intense fighting in the 10 days of bombings and airstrikes between Israel and Hamas.
Palestinian medical and security sources say 240 people have been killed in Gaza, including at least seven children who died Thursday, and about 1,800 injured. Israel says one of its citizens has died.
A statement from the Israel Defense Forces said: "The IDF's objective as defined by the Israeli government is to establish a reality in which Israeli residents can live in safety and security without continues indiscriminate terror, while striking a significant blow to Hamas' terror infrastructure.
"This stage of operation 'Protective Edge,' led by the IDF's Southern Command, will include close coordination between IDF units including infantry, armored corps, engineer corps, artillery, and intelligence combined with aerial and naval support. This effort will also be supported by the Israeli Security Agency (ISA) and other intelligence organizations."
Before the ground operation was launched, Gaza experienced one of the worst nights of fighting Thursday since the war began after a temporary cease-fire ended, CNN reporter Ian Lee said.
"Periodic fire balls illuminate the sky over Gaza," he said. "We see rockets screech toward the sky. Minutes later we see an intercepting missile rise from the iron dome, reducing the rocket into confetti of light and fire.
"We've seen red tracer rounds fly across the horizon. The repetitive thud of naval guns echoes throughout the coastal strip."
A 4-year-old girl was killed in an Israeli airstrike near the customs building in Khan Younis, Palestinian medical and security sources said, and another airstrike killed a 29-year-old man east of Khan Younis.
Aqsa TV reported that an Israeli was killed and another injured in shelling of Ashkelon and that seven Israeli soldiers were injured in an attack on a military location.
Aqasa TV also reported that Israeli gunboats near Baiet Lahiya north of Gaza strip, fired at the homes of residents.
During the cease-fire, at least three mortar shells were fired from Gaza, injuring an Israeli soldier, Israeli military sources said.
CNN's Ben Wedeman said late Thursday that flashes coming from artillery of tank fire could be seen along the eastern border in the direction of Khan Younis and to the east of Shajai'a.
These flashes were preceded by a series of air strikes on the Zaitoun neighbourhood of Gaza City, he said.
"There is more incoming than we've seen in the last 10 days," he said.
Despite those incidents, U.N. Secretary-General Ban Ki-moon said both sides had "mostly respected" the temporary cease-fire between Hamas and Israel. The United National requested the five-hour lull for humanitarian reasons.
"The pause shows that a cessation of hostilities is possible if all the parties demonstrate the necessary will and put the interests of civilians, who have borne the brunt of this escalation, first," Ban said in a statement.
At least 235 Palestinians have been killed and close to 1,769 have been injured since Israel began its anti-Hamas military operation July 7, according to Palestinian health officials.
Amid all the military action, the Israeli Cabinet planned to meet at 11 a.m. Friday.
In Cairo, Palestinian Authority President Mahmoud Abbas and Arab League Secretary-General Nabil Al-Arabi held talks Thursday aimed at reaching a cease-fire agreement.
An Israeli delegation also attended, leaving after several hours, the state-run al-Ahram news agency reported.
"I expect that we will reach an agreement very soon; the efforts of a cease-fire is to stop the bloodshed, killing and destruction in Gaza," said Nabil Shaath, an Abbas adviser and member of the central committee of the Palestine Liberation Organization.
He said negotiators were focusing on stopping bloodshed above all else. He said they would later discuss Hamas demands, including opening Gaza border crossings and freeing prisoners whose exit from jail was negotiated in exchange for the release of Israeli soldier Gilad Shalit.
"These are all legitimate demands by Hamas, but the priority is for an immediate cease-fire," Shaath said.
Hamas leaders had rejected an earlier Egyptian cease-fire proposal, saying they had not been consulted on the deal and complaining that it did not address their broader demands.
Hamas officials had said Wednesday they would not participate in the Cairo talks, but PLO official Saeb Erakat -- who was in the Egyptian capital with Abbas -- said the Palestinian Authority leader had met with representatives of Hamas and Islamic Jihad.
Erakat said negotiators are trying to extend the U.N.-sponsored temporary humanitarian cease-fire on a "rolling basis."
"While there is no plan at this point for a comprehensive cease-fire agreement ... we are trying to extend the current one by another six or 10 hours, or even several days if possible," he said.
Egypt is playing a large role in the talks despite its distrust of Hamas.
Like Israel, Egypt considers Hamas a terror organization because of the group's roots in the Muslim Brotherhood, which Egypt's military-led government banned after the country's 2013 coup.
During Thursday's temporary cease-fire, Gaza banks opened for the first time in 10 days. Residents poured into the streets.
Red Cross officials visited hospitals and damaged houses to assess medical needs, and worked with local officials to fix water pipelines. Some work was also done to repair power lines, the United Nations said.
At least 10 to 15 trucks entered Gaza through the Karem Shalom border crossing once it opened at 1 p.m. (6 a.m. ET), according to Ra'ed Fatooh, the Palestinian official in charge of the crossing in Gaza.
Goods were limited to medical supplies and basic foodstuffs such as rice, sugar, oil, canned food, flour and other basic goods, he said.
"The trucks are being subjected to strict and difficult search by the Israeli security before entering the crossing," he said.
The search, he said, illustrated one of the chief complaints of Gaza residents -- fluctuating border controls that often stymie the flow of goods into the territory.
"We want the crossing to open in a normal fashion to go back to how it was before 2007 and to bring the required goods and products for Gaza for the people and residents to live in dignity as the rest of the world," Fatooh said.
Deaths on Gaza beach
Fallout continued Thursday from the deaths the day before of four cousins ages 9 to 11 who died in an Israeli military strike on a Gaza beach.
The results of a preliminary investigation suggests the deaths were the result of a "a tragic misidentification of the target," a spokesman for Israeli Prime Minister Benjamin Netanyahu told CNN on Thursday.
"We didn't want to kill those four boys. That was not our intention," Mark Regev said. "I'd even say the opposite is true. Had we known that that missile was aimed at four young men like that we would have not sent the missile."
A Hamas official called the killings a "war crime."
"Those children were not firing rockets, they were just playing," Hamas spokesman Sami Abu Zhuri told reporters Wednesday.
Regev, however, said a legitimate Hamas target was nearby, highlighting what he called a "complex combat environment" in crowded Gaza City and surrounding areas.
Israeli officials say militants often use mosques, schools and other crowded places to hide rockets and other weapons.
Indeed, the U.N. Relief and Works Agency said it had found 20 rockets hidden in a vacant school in Gaza, the first time the agency had made such a discovery.
The group didn't say who placed the rockets there but condemned the act as a "flagrant violation" of rules meant to keep U.N. aid workers safe.
For the hundreds of people gathered for the boys' funeral Wednesday, however, the legal and ethical arguments made little difference.
"I felt as if the world had come to an end when I heard the news," said Ramiz Bakr, the father of one of the boys. "I wish I had died before hearing he was dead."
CNN's Ben Wedeman reported from Gaza City, and CNN's Michael Pearson reported and wrote from Atlanta, while Jethro Mullen reported and wrote from Hong Kong. CNN's Ali Younes, Samira Abdelaziz, Kareem Khadder, Tim Lister, Ian Lee, Diana Magnay, Samira Said, Michael Schwartz, Salma Abdelaziz and Tal Heinrich also contributed to this report.
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