DAKAR (Reuters) - Barefoot children in tattered clothes scramble through the dusty, trash-strewn streets of Dakar, tapping on car windows and shadowing market-goers in the hopes of a few coins or a cup of rice.

The sight of young people begging is not uncommon in a country struggling with deep-rooted poverty, but in the West African state of Senegal there is a twist.

These children are students in the nation's traditional Koranic school system being forced by teachers to panhandle on pain of severe beatings, according to an investigation by global advocacy group Human Rights Watch released on Thursday.

"There are at least 50,000 children just in urban residential daaras (Koranic schools) that are living in conditions akin to slavery," said study author Matt Wells.

"We're talking about quite a serious problem here in Senegal and the numbers are increasing every day," he said of the "talibe", or scholars.

The findings are troublesome in a mainly Muslim nation of 12 million where Koranic schools have existed for centuries, placing Senegal on a list of countries with severe forced child begging such as Pakistan, India, and Albania.

The Senegalese government has passed laws in recent years targeting the problem but has been slow to enforce them amid fear of a backlash led by the politically powerful religious leaders benefiting from the begging, according to a government official quoted anonymously in the report.

"There has been a sense that this issue is too sensitive to touch, but one of the hopes of this report is to push through that," said HRW's Wells.

Minister of Religious Affairs Mamadou Bamba Ndiaye said the state was seeking solutions to forced child begging.

"We don't support the fact that children are being thrown into the streets like this," he told Reuters by telephone.

LEGACY OF STREET CHILDREN

Suleiman can't remember his age, but he knows he was forced to beg for eight years as a talibe in a Dakar-area daara and was beaten repeatedly by his teacher before seeking refuge at a shelter this week.

"He would beat me with an electrical cord," he said. "It was very difficult to collect the money."

Parents in Senegal have been entrusting their children to daaras for centuries, expecting them to receive food, shelter and teachings from the Koran in exchange for their work on communal farms during the harvest.

But forced begging began to emerge in Senegal's daara system in the 1970s when crop failures led schools to move into the cities and boarding students were called upon to panhandle to cover the daara's costs.

Since then, the majority of Senegal's urban daaras have embraced forced begging, Wells said, with some of the religious leaders -- known as marabouts -- making as much as $100,000 per year on the proceeds while cutting back hours in the classroom.

"In a country where people generally live on $2 per day, that is an incredible sum," Wells said.

Human Rights Watch said many of the country's several hundred thousand talibes are forced into the streets to beg for eight hours a day, and are given strict quotas for amounts of money, rice and sugar to be gathered.

If they come up short, they are beaten.

"The child is taken to a room, his shirt is stripped off either by the marabout or a grand talibe, and he is beaten, often brutally," said Wells.

"This has created a legacy of street children in Senegal," said Wells. "Because of the severe abuse they suffer at the hands of the marabout, they run away in huge numbers."

Ousmane Sonko, who runs the Children's Empire shelter in Dakar, said parents sometimes resist taking their children back because they do not believe the marabouts are abusive.

While forced child begging exists elsewhere in the region, the problem is most pronounced in Senegal where alms-giving is an important cultural and religious act, Wells said. As a result, many children are smuggled in from Guinea Bissau, Guinea, and Gambia to beg for daaras in Dakar.

"There are people (in Senegal) to which the tenet of the Islamic faith, zakat, is incredibly important, so it has become easy for these unscrupulous marabouts to make a lucrative gain off the backs of the children," Wells said.

Human Rights Watch said it was calling on the government of Senegal to crack down on forced begging