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The image of a dead preschooler cradled by the prime ministers of Egypt and Gaza in a hospital hallway Friday has drawn attention to the dangers Gaza's children face in this crowded urban battle zone.

Children make up half of Gaza's population of 1.6 million and seemed to be everywhere in the current round of cross-border fighting between Israel and Gaza's militant Hamas rulers.

Children loitered Friday outside a Gaza City morgue for a glance at the latest "martyrs." Others followed adults to funerals or even rushed to the site where Israeli missiles had just struck a government building and fire was still smoldering. Despite outward bravado, young boys of elementary school age said quietly that fear of airstrikes kept them awake at night.

So far, six of 28 Palestinians killed in Israel's offensive this week have been children, ranging in age from just under 1 to 14 years, according to Gaza health officials. Most were killed by shrapnel while in or near their homes. In Israel, 12 children were hurt in rocket attacks this week.

Israeli Prime Minister Benjamin Netanyahu has accused Hamas of using Gaza's civilians, particularly children, as human shields by launching rockets from crowded residential areas.

Gazans argue that Israel is unleashing massive airstrikes on their territory without regard for civilians. They say that even Israel's self-described surgical strikes on militant targets put civilians at grave risk in Gaza, one of the world's most densely populated places.

Mahmoud Sadallah, the 4-year-old Gaza boy whose death moved Egypt's prime minister to tears, was from the town of Jebaliya, close to Gaza City. The boy died Friday in hotly disputed circumstances.

The boy's aunt, Hanan Sadallah, and his grief-stricken father Iyad — weak from crying and leaning on others to walk — said Mahmoud was killed in an Israeli airstrike. Hamas security officials also made that claim.

Israel vehemently denied involvement, saying it had not carried out any attacks in the area at the time. Gaza's two leading human rights groups, which routinely investigate civilian deaths, withheld judgment, saying they were unable to reach the area because of continued danger.

Mahmoud's family said the boy was in an alley close to his home when he was killed, along with a man of about 20, but no one appeared to have witnessed the strike. The area showed signs that a projectile might have exploded there, with shrapnel marks in the walls of surrounding homes and a shattered kitchen window. But neighbors said local security officials quickly took what remained of the projectile, making it impossible to verify who fired it.

Mahmoud's 12-year-old cousin Fares was injured in the right leg by shrapnel and was still visibly shaken several hours after the incident. "It's terrifying. I don't sleep at night," the boy said of the massive Israeli air attacks of the past three days. "I'm staying up all night."

Mahmoud's body was taken to Gaza City's main Shifa hospital around midmorning, just as Gaza Prime Minister Ismail Haniyeh of Hamas was showing Egyptian Prime Minister Hesham Kandil around the wards of patients.

One of the Sadallah's neighbors, carrying the lifeless boy, pushed through a throng of Hamas security men to reach the politicians. Eventually, the two prime ministers were photographed cradling the child.

Fighting back tears, Kandil called on Israel to halt its offensive.

"What I saw today in the hospital, the wounded and the martyrs, the boy ... whose blood is still on my hands and clothes, is something that we cannot keep silent about," he said.

In the propaganda war between Israel and Hamas, the suffering of children has served as a powerful tool.

Israel has repeatedly accused Gaza militants of cynically exploiting children. Netanyahu alleged Thursday that "Hamas deliberately targets our children, and they deliberately place their rockets next to their children."

On Thursday, a rocket attack on an apartment building in the southern Israeli town of Kiryat Malachi wounded a baby and a 4-year-old child, along with killing three adults. Photos showed rescuers evacuating the baby, who was covered in blood. In addition, 10 children have been hurt by shrapnel, Israeli paramedics said.

The rockets fired from Gaza are relatively crude and Israel says their main purpose is to instill fear and harm Israeli civilians. Since Wednesday, Gaza militants have fired hundreds of rockets, killing three Israelis and paralyzing large areas of the country where civilians were ordered to stay close to home or bomb shelters. The fighting has forced tens of thousands of Israeli children to stay indoors, and schools in southern Israel have been closed for the past two days.

Israel, meanwhile, has pounded Gaza with dozens of rapid-fire airstrikes, with loud booms ringing out, sometimes just minutes apart. Few civilians ventured into the streets Friday, particularly after dark. In Gaza City, a tractor-pulled cart loaded with women and children had a white flag dragging on the ground behind it, presumably as an extra precaution.

Some of the Gaza boys trying to get close to the "action" put on a brave face.

"I'm not afraid of the rockets the Jews are firing," said 10-year-old Mohammed Bakr, waiting outside the Shifa Hospital morgue for bodies to arrive. But, he acknowledged, "I like it better when it's quiet."

Mohammed and his cousin, 12-year-old Udai, said they had seen many dead bodies, including during Israel's last major offensive in Gaza four years ago. Both boys come from large families, as is typical in Gaza — Mohammed said he has nine siblings and Udai has six. Overwhelmed parents often find it difficult to keep tabs on all their children in dangerous times.

"Our parents tell us to stay home, but we don't," said Mohammed with a smile. "We want to see the martyrs."

Earlier, another group of boys tried to get closer to the ruins of a former Hamas government building, with smoke still rising from an Israeli strike. Hamas policemen tried to push them away, shouting that there was concern about unexploded ordnance.

Adults often pressure children not to show fear. Asked if they were scared, several boys waiting for Mahmoud's funeral procession to begin nodded. However, when an adult showed up and told them that Gazans are not afraid, they quickly stopped talking.

Child psychologists say the trauma of war stays with Gaza's children for a long time.

Hussam Nunu, the head of Gaza's Community Mental Health Program, said close to a third of the about 1,500 patients treated every year are children affected by stress and violence. After Israel's last offensive four years ago, the number of children suffering from post-traumatic stress disorders was "overwhelming," he said.

"Since then we have done a lot of outreach, but when another escalation like this happens, our work can be undone," he said.