Twelve-year-old Bhola worked more than 15 hours a day for two years without being paid or allowed to visit his parents. On Thursday, a local non-governmental organization freed him and 49 other such children.

The children, all boys ages eight to 14, are sons of poor farm laborers in eastern India's Bihar state. They had been brought to New Delhi to work in small factories making elaborately embroidered fabric called zari.

The embroidery requires working with glittering synthetic fibers and tiny needles, with which the children often hurt themselves.

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"We freed these 50 children after some frantic parents came to us saying that they were unable to get in touch with their children," said Kailash Satyarthi of Bachpan Bachao Andolan, or Save the Children Mission, the group that freed the young workers.

Despite India's growing economic power, child labor remains widespread there. An estimated 13 million children work, many in carpet-weaving or more dangerous industries like glassmaking, where such labor has been banned since 1986.

Earlier this year, India also banned hiring children under 14 as household servants or workers in restaurants, tea shops, hotels or spas.

But such laws are still flouted in small factories and businesses throughout the country, including dangerous firecracker-making plants. The children are usually poorly paid, underfed and often beaten.

Critics of India's child labor laws say the bans have had limited effect because they do little to realistically address the poverty at the root of the problem.

For the children, the issue is not as clear-cut as many outside India would think. They come from bitterly poor families and have little or no access to primary education. In many cases they are their families' sole breadwinners.

On Thursday, the newly freed children told reporters they had often been slapped and whipped with leather belts.

"For two years these children have worked for free," said Satyarthi. "This is a sort of slavery."

"There are a million such places where the child labor laws are laughed at," he said.

Charges have been filed against the owners of the factories where the children worked, but all three had apparently absconded. No other details were immediately available from the local police.

Bhola, who goes by one name, said he had worked from 8 a.m. to midnight most days, with two short meal breaks. At night, 15 to 20 boys slept in the same workroom.

"If we made mistakes, the owner would beat us with a belt and we would be given food once early in the morning and then at the end of the day," Bhola said.

His father, Ram Munyasa, had agreed to send him to New Delhi based on a middleman's promises that his son would get an education and a monthly salary of at least 3,000 to 4,000 rupees, or $65 to $80.

"Every few months, I would ask him why my son wasn't sending any money and I would be told that his work hadn't started yet. Finally I had to come to Delhi searching for him," Munyasa said.

Next to Bhola sat Ashraf, who said he is 11 but looked much younger. The Save the Children Mission has yet to find his parents. Until then, he will stay in a children's home. When asked what he wanted to do now that he is free, he said, "I want to go home to my mother."