WITH a whine and an earth-shaking thud, another Israeli artillery shell lands in a field near a Gaza school. Daoud looks up from his books and gets ready for the race.

When lessons are over the ten-year-old Palestinian and his schoolmates will run across farmland, hoping to salvage the unexploded missile, to sell for a few shekels to feed their families.

Since Israel and international donors cut off the Hamas-led Palestinian Government, unpaid salaries and border closures mean that poor families rely on their children digging through strawberry and cucumber fields that have turned into artillery ranges.

It is a dangerous living. Three teenagers were killed last week when a shell exploded at their home in Beit Lahiya, northern Gaza. Relatives say it went off as Muhammad Qassem, 18, Mustafa Qassem, 19, and Araf Zaranda, 15, removed the 45kg (99lb) round from their farm, to turn over to Palestinian police. Others believe they may have been trying to retrieve the intact explosives for militant groups.

But in nearby Jabaliya, Daoud Thari and his friend, Younis Dardona, are blasé about the risk. Two or three days a week they casually risk their lives digging through the sandy earth to retrieve the unexploded shells — 45kg metal casings nearly half their height that they can barely manhandle into the basement of their home.

If a shell’s detonator is still intact, they screw it off and empty the explosive powder before selling the metal to scrap dealers, or turn it into an ornament for wealthier neighbours to buy.

“We wait until after school, when they have stopped firing, then we start digging them out of the ground,” said Daoud, a prize-winning student whose jobless father has no other means of support.

“We aren’t afraid. The Beduia boys who live there go every day. Sometimes we fight for them. It helps my family if I can earn some money. We sell the light ones for 20 shekels (£2.50) and the heavy ones for 40 shekels.”

Reacting to a deepening humanitarian crisis, the UN and aid agencies increased their annual emergency aid appeal this week, from $215 million (£116 million) to $385 million for relief in Gaza and the West Bank. The “creeping despair” described by one senior UN official is felt hardest in Gaza, where tit-for-tat shelling has become a daily reality since Israeli settlers pulled out last autumn.

Concerned that the Palestinian Authority could disintegrate under the strain, leading to instability and bloodshed, donors are urgently seeking ways to channel aid to Palestinians, bypassing Hamas.

In Brussels Scott Carpenter, Deputy US Assistant Secretary for Near Eastern Affairs, spoke of “emerging consensus” on a special fund and hoped that a mechanism would be agreed within three to four weeks.

But disagreement remains between Washington hawks, opposed to any payment of government salaries, and those urging that Palestinian Authority staff, such as doctors, be paid before medical and welfare services grind to a halt. Israeli military officials this week accused the authority of cynically trying to create the “illusion of a humanitarian crisis”.

Each month Palestinian militants launch 80-90 of the inaccurate but potentially deadly Qassam rockets. Israel strikes back with artillery batteries that have pounded Gaza with more than 5,000 shells in recent months.

Both sides insist that their firing is retaliatory. Israel is determined to stop militants striking civilian homes in border towns, while militants say that they are avenging Israeli helicopter attacks that have killed civilians. In an ironic twist, the Qassams are sometimes the bastard offspring of Israel’s own munitions.

Militants pack the explosives from dud shells into their own rockets. “We use it back against the Israelis,” one al-Aqsa Martyrs’ Brigades member said in Jabaliya.

Since the Israeli shelling began a few months ago it has killed six Palestinians. Six Israelis have been killed in the past five years by Qassams. Israel intensified the shelling in April and claims to have reduced the Palestinian fire.

A military official said: “Obviously our response is going to take into consideration population density. We take into account the potential harm that might be caused to the civilian population, but at the same time one has to remember that with a combat-like situation, when you are being fired at all the time, you have to fire back.”

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