Fierce fighting between Israeli troops and Hamas militants continued near Gaza City on Monday as the death toll from the conflict rose above 500.
Heavy bombardment hit areas east of the city, particularly the neighborhood of Shaja'ia, where a large Israeli assault Sunday contributed to the deadliest day of the war so far.
As clashes escalated over the weekend, Hamas said it had captured an Israeli soldier - a claim Israel later denied.
With no sign of either side backing down in a conflict in which most of the victims have been civilians, U.S. Secretary of State John Kerry is due to arrive in Egypt on Monday to push for a cease-fire.
Speaking to CNN's "State of the Union" on Sunday Kerry said that the United States supports Egypt's initiative for a truce and "will work for a fair cease-fire."
The United States has "shown our willingness to try to deal with the underlying issues," but Hamas "must step up and show a level of reasonableness," he said.
"No country, no human being, is comfortable with children being killed, with people being killed, but we're not comfortable with Israeli soldiers being killed either or with people being rocketed in Israel," Kerry said.
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Deadly clashes broke out after Israeli tanks drove into Gaza and launched a ground operation that escalates the conflict with Hamas.
The incursion Thursday night follows 10 days of Israeli bombardment of Gaza that has killed more than 250 people. Israel launched the aerial offensive last week, saying it aimed to halt the firing of Hamas rockets from Gaza into Israel.
Israeli Prime Minister Benjamin Netanyahu and Defense Minister Moshe Yaalon ordered the ground operation to destroy tunnels dug from Gaza into Israeli territory, according to a statement.
Thirteen Hamas militants used a tunnel earlier Thursday to launch an attempted attack in Sufa, near an Israeli kibbutz, but were stopped by Israeli soldiers, the Israel Defense Forces said.
The IDF said it had sent a "large" force into Gaza that includes infantry, tanks, artillery, combat engineers and intelligence units, with aerial and naval support.
CNN's Wolf Blitzer asked Mark Regev, Netanyahu's spokesman, whether Israel planned to occupy Gaza for a long time.
Regev didn't answer directly, but said Israel's goals are to "diminish" the Hamas military force and to show that it cannot attack Israel with impunity.
You can follow all the developments at CNN.com.
FROM CNN WIRES:
After putting himself in the middle of the historic tensions between Israelis and Palestinians this week, U.S. President Barack Obama on Friday wraps up his first trip to Israel since becoming president. He then moves on to another of America's closest allies in the region - Jordan, a military and intelligence partner, which has been facing trying times.
Obama is devoting his last hours in Israel and the Palestinian territories to cultural endeavors.
With Israeli President Shimon Peres and Prime Minister Benjamin Netanyahu, the president and Secretary of State John Kerry visited the grave of Theodor Herzl, the father of modern Zionism, where Obama placed a stone on top of the tomb.
From there, the delegation went to the grave of Yitzhak Rabin, the former Israeli Prime Minister who was assassinated in 1995. Obama also laid a wreath and a stone there. The stone for Rabin's grave came from the grounds of the Martin Luther King, Jr. memorial in Washington.
Obama and the Israeli leaders also visited the Holocaust memorial Yad Vashem, where the president turned up the "eternal flame" of remembrance of the 6,000,000 Jewish victims of Nazi death camps in World War II.
Before continuing on to the last stop of his trip, Obama with visit the Church of the Nativity in Bethlehem, which is on the West Bank, with Palestinian President Mahmoud Abbas.
Obama then travels to Jordan, where he will meet with King Abdullah II, who has faced harsh criticism lately from his country's people.
READ MORE: Obama travels from Israel and Palestinian lands to Jordan
Today, President Obama is in the West Bank city of Ramallah for the second leg of his historic Middle East visit. He is meeting with Palestinian President Mahmoud Abbas to discuss the possibility of reviving peace talks in the region. The president has said he is prepared to listen, and hasn't come with a peace plan. The two leaders will talk at a working lunch and will then address the media.
But the trip is already marred by violence. Two rockets fired from Gaza landed in the southern Israel city of Sderot hours earlier, while the president was about 60 miles away in Jerusalem. There are reports of property damage but no injuries.
Stuart Holliday, president and CEO of the Meridian International Center and fmr. former U.S. Ambassador special political affairs to the UN Security Council, weighs in on Obama’s meeting with Abbas today and how the attacks may have affected it. Holliday says the rocket attacks are a reminder that the Palestinian Authority does not control Gaza and that the Palestinian government is divided, highlighting "the weakness that we face in terms of the talks restarting."
Holliday calls the president's trip a significant visit, but notes that the Palestinians are very skeptical about what the president hopes to accomplish. “I think it's a mixed bag,” Holliday says. “But I do believe that they would view the president's visit, and the look for any opportunity to get these talks restarted. And of course, they've been on the sidelines, waiting for what they see as a critical issue, for these settlements to halt. Whereas Israelis have said, look, ‘we're ready to talk at any point as long as you don't put preconditions on these talks.’”
Today, President Obama is in the West Bank city of Ramallah for the second leg of his historic Middle East visit. He arrived from Jerusalem this morning, making a 10-mile trip between two Middle East cities that are worlds apart.
The trip is already marred by violence. Two rockets fired from Gaza landed in the southern Israel city of Sderot earlier, underscoring the urgency of the visit. It happened just a few hours ago while the president was still in Jerusalem, about 60 miles away. There are reports of property damage, but no injuries.
The president is in Ramallah to meet with Palestinian President Mahmoud Abbas. The two leaders will talk at a working lunch and will then address the media.
Later today, President Obama returns to Jerusalem for a state dinner in his honor hosted by Israeli President Shimon Peres.
Chief White House Correspondent Jessica Yellin is live from Ramallah with the latest on how the rockets may have affected what the president hopes to accomplish today.
President Obama arrives in Ramallah for his first visit to the West Bank since becoming President of the United States.
Jessica Yellin is live from Ramallah. John King is live from Jerusalem.
President Obama arrives in Tel Aviv for the start of a historic Middle East visit today. He is scheduled to meet separately with Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas during the trip. The president is expected discuss the United States’ commitment to preventing a nuclear-armed Iran with Netanyahu and restarting negotiations between Israel and Palestine.
His plane lands in less than 90 minutes but his mission is taking on a new urgency at this hour because there is mounting evidence the Syrian government has used chemical weapons on its own people near the city of Aleppo.
Sara Sidner is live in Jerusalem for "Early Start" this morning with the latest on how developments in Syria might affect the president’s agenda on this trip.
After eight days of fighting between Israel and Gaza, a cease-fire established Wednesday appears to be holding. Egyptian President Mohamed Morsy played a central role in the talks for a truce with Israel, and emerged as a major leader in the Middle East. The agreement, meanwhile, also demonstrates the diminishing role of the Palestinian Authority and the rise of Hamas.
But this morning, new violence erupted after reports Israeli troops opened fire in a buffer zone with Gaza, killing at least one Palestinian and wounding 19, Hamas security and health officials said.
Will the latest violence threaten the fragile cease-fire?
Stuart Holliday, fmr U.S. Ambassador for Special Political Affairs to the United Nations and current President and CEO of the Meridian International Center, weighs in on "Early Start" this morning.
Serious bargain hunters are on the prowl today, lined up to grab the best of the Black Friday doorbuster deals. But a new challenge faces them this year as many stores moved their doorbuster hours up to Thanksgiving night. Some shoppers camped out on line for hours to gain a competitive advantage. CNN’s George Howell reports from Atlanta on "Early Start" this morning.
Less than 48 hours after a cease-fire went into affect between Israel and Hamas, violence unfolded in Gaza near the Israeli border today killing at least one Palestinian and wounding 19, Hamas security and health officials said.
Both sides claimed a victory after the cease-fire was declared on Wednesday, allowing a respite after air strikes and rockets bombarded the region for eight days. The focus now is on keeping the fragile peace.
CNN’s Sara Sidner has more live from the CNN Bureau in Jerusalem.
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