On the wealthy streets of Jeddah, in Saudi Arabia, thousands of young child-beggars, under the auspices of ruthless gangmasters, are simply trying to survive.
Many hail from countries like Yemen which, despite bordering one of the Middle East's richest states, is a world away in terms of economic prosperity.
These children are often sold by families who are either duped into believing their offspring will get a better life or sometimes simply threatened.
Once in the country, they are likely to face beatings and are sometimes even mutilated as their Dickensian masters stoop to any low to try to improve the chances of them earning more money.
The Ministry of Social Affairs in Saudi Arabia's western province has a unit dedicated to picking up children who are illegal in the country.
It is tasked with taking these children from the streets and then investigating their stories. Efforts are made to try to find their families but often no relatives are found.
In such cases, these youngsters are deported as illegal aliens back to their country of origin.
But to bring these children in, the unit must carry out night-time swoops to find children begging without families. When these children are found, they are often frightened and desperate to get away from the Saudi officials.
One child found by the team during a raid, Ali, is a typical victim of the slavery business.
Initially, he attempted to convince officials that he was in the city with his brother. However, it soon became clear that this was not the case.
Eventually, Ali revealed that he slept under a bridge or in "any house" he could find. He avoided using shoes, to boost his chances of getting money.
While the details of Ali's story are sketchy, we know that Ali was smuggled across the porous border between the Yemen and Saudi Arabia.
In 2005, the Yemeni Ministry of Social Affairs acknowledged that about 300 children were crossing the border every month.
It is not always possible to know the entire truth about these children but what is clear, is that they are working for others, out of education, and kept in a cycle of poverty and danger.
Ali told officials at the shelter: "I was smuggled in, in order to beg. I told him (the gangmaster) I don't want to beg, so he beat me up."
The boy said he ended up begging because of physical abuse involving metal wire attacks to his back.
He also said he was forced to beg all day, but claimed that he only gave some of his earnings back to his paymaster.
Such is the scale of the problem that a centre to house rescued children has been opened in Yemen at the Harad Border Crossing.
Ali now faces an uncertain future
That is Ali's most likely destination.
The precise truth of his story will probably never be known. Even officials in the shelter do not really believe the account he has given them, citing inconsistencies with earlier interviews.
Those brought to the shelter have often been schooled to give some sort of false story about having families in Saudi Arabia.
The children caught are almost entirely boys and although many come from Yemen, others come from countries such as Somalia, Sudan, Chad, Pakistan and India.
Yemen has become more involved in child trafficking since its workers were expelled from Saudi Arabia in the 1990s following the first Gulf War. Children were sent instead because Saudi authorities do not prosecute children.
Meanwhile, the future for Ali is uncertain. A delegate from the Yemeni Embassy will visit the shelter to pursue Ali's case and try to trace his family.
In all likelihood, he will be deported back to his country of origin, but with the trade of children continuing to rise, Saudi officials will probably be meeting many more like him.
This World: Child Slavery with Rageh Omaar was broadcast on Monday, 26 March, 2007 at 2100 BST on BBC Two.