LONDON - A few weeks before his own death, Bilal el-Essi took a photo of another man’s body, sprawled under a women’s bike in a Gaza City street, a a child’s pink backpack fallen from the basket.

The man was killed trying to find food for his family, Essi told friends and family when he shared the image, a snapshot of the tragedy and desperation in Gaza City.

Essi knew the terrible pain of not being able to feed the people you love, and it got sharper every day that he could not find milk for his two girls, five-year-old Layan and two-year-old Mila, or bread for his father.

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So when he heard that a rare delivery of food aid might reach northern Gaza in the early hours of Thursday, he made his way to the seafront Al Rashid Road with two brothers, their cousin Moataz el-Essi told the Guardian by phone from Germany.

Bilal, a football-mad 28-year-old who was quick with a joke, joined hundreds of people huddled around small fires waiting in the bitter cold for the trucks of food.

Shukri Fleifel, a 21-year-old photographer and filmmaker, was also in the crowd. He had watched Israeli forces open fire on people waiting for aid trucks in the same spot just a few days earlier, he said. But like everyone else in Gaza City, he was hungry.

“There is quite literally nothing available to buy in the markets,” he said in a phone interview. “People have been forced to resort to animal feed, but even that is scarce.”

The head of the UN agency for Palestine, Philippe Lazzarini, this week said northern Gaza was enduring a siege within the broader blockade of Gaza, with its 300,000 remaining residents getting even less aid than the south of the territory. “When we talk about the pockets of looming starvation, famine, we primarily refer to the north.”

Fleifel said that around 4.30am, in the pre-dawn darkness, he saw two Israeli tanks drive down Al Rashid Road, firing into the air to disperse the crowds. Moments later came the sound of trucks. “People knew that the much-anticipated flour had finally arrived.”

But as they rushed towards the vehicles, he noticed another Israeli tank appeared to the north, between Nabulsi and Sheikh Ijleen junctions. Moments later, it opened fire, he said, and the crowd also came under attack from the south.

After the initial attack, the tanks withdrew south, he said, but kept attacking the hungry crowd. “They used stun grenades and fired indiscriminately, from a considerable distance, towards citizens who were still making their way towards the aid trucks.

“I saw people collapsing beside me, some injured and some already martyred.” He threw himself between two concrete benches and when the firing ended, was astonished to find he was unharmed.

Fleifel is a commercial photographer who turned to war journalism when his home came under attack but even after months of filming Israeli attacks, the bloody scenes around him seemed worse “than anything depicted in a horror movie”.

He watched as the wounded and dead were taken to hospital, many piled on carts pulled by donkeys or horses because there were no ambulances.

Israel’s military says most of the dead were killed in an initial crush as crowds stormed the aid trucks, and soldiers passing through the area later “opened fire only when they encountered danger”, shooting only in self-defence, not into the crowd.

Fleifel said people were crushed in the incident, but claims only after the crowd came under Israeli attack. “The stampede and chaos was caused by the [Israeli] occupation forces opening fire,” he said.

Essi was separated from his brothers in the panic that broke out after the first bullets hit the crowd, as everyone raced for cover, Moataz said. When the gunfire tailed off, his brothers searched frantically through the crowd and found him, bleeding badly from a wound in the neck.

He survived a slow journey to hospital along devastated streets, but died in al-Shifa hospital later; one of the brothers who took him there and was with him when he died told Moataz the injury was caused by a bullet.

His brothers and father are left with their grief and their guilt. “They are heartbroken they didn’t stop him going out to look for food,” Moataz said.

“Some of his brothers had fled south, including one who is an orthopaedic and trauma doctor. He feels that surely, if he had been there, he would have been able to help him.”

Essi, a graduate with a good job at his uncle’s furniture company, had lost his mother to cancer three years earlier, a death the family says was hastened by Israeli restrictions on medical imports, or on patients leaving Gaza for treatment.

He stayed in Gaza City to look after his father, because he refused to leave his home even when Israeli forces ordered an evacuation, his cousin said. Always devoted to his family, he was killed trying simply to keep them alive.