From CNN's Mallika Kapur

Chennai, India - Beaten with rods, belts and subjected to other forms of abuse, the bonded laborers toiled away in a tiny brick kiln in southern India day after day with little hope of freedom and escape.

But on a tip, officials from the government of Tamil Nadu state in India raided the kiln. What they found shocked them: More than 500 people living and working under a brutal and oppressive system.

"We worked all the time. We would only stop to eat," says 20-year-old Dambru Jani, who was rescued in the raid. "If we tried to rest, they'd abuse us and force us to work again."

Saju Mathew is the national director for the International Justice Mission, the human rights group that assisted the government with the raid. He said that even though India banned bonded labor in 1976, the practice of paying back a loan or advance with work, not money, still exists.

"The key thing you look for is, are they free?" says Mathew. "What you realize in bonded labor is that the owner decides when they eat, when they sleep, whether they are free to leave or not. All the terms of their life are now dictated by the owner."

In this instance, the laborers were given a cash advance of 10,000 rupees, or about $225, each. They were then taken hundreds of miles away from home to work at the brick kiln.

Which is where government official S. Kandaswamy, along with police authorities and the International Justice Mission, raided the kiln and took the owner by surprise. The raiders themselves were taken aback, too. Expecting to find around 200 people inside, they found instead more than 500, including women and children.

"More than 14 hours a day they are working," Kandaswamy said. "Sometimes, they are being beaten, and some harassment was noted by the laborers. No medical facilities. ... Bonded labor is against humanity, so it has to be curbed."

The owner of the brick kiln was held and released. The authorities have three months to file charges.

The government organized trucks to send the laborers to a school nearby, where they were given meals, police protection, medical treatment and counseling. They also given a certificate of freedom and a thousand rupees, or about $25, which is the first installment of rehabilitation funds the government will provide.

Special trains were also organized which gave the freed workers a ticket home.

Part 2: CNN's Mallika Kapur travels to the workers' homes to see how they're coping after being rescued.