CHENNAI, INDIA - After his rescue from abuse and overwork as a bonded laborer in a brick kiln in south India, Shanmugam Paneer has set up his own business making household items from bamboo.

But the lifeless monotone he uses to describe his five-year ordeal betrays an inner struggle to move on from one of India's most prevalent forms of human trafficking.

"For many, the process of coming out with the truth is far more painful than actually living those years in bondage," said Loretta Jhona, a counselor with the U.S.-based charity International Justice Mission.

"Freedom becomes an alien concept and they constantly battle with their captivity mentality."

Though India banned bonded labor in 1976, it remains widespread, with millions working in fields, brick kilns, rice mills and brothels, or as domestic workers to pay off debts.

India announced an ambitious goal last year to rescue more than 18 million bonded laborers by 2030 and to increase fivefold the compensation that is paid to them, as part of a wider drive to tackle modern slavery.

Rescued workers need more psychological help to become truly free, counselors say, as they are often too scared to admit to suffering, such as sexual abuse, for fear of retribution from their former owners.

Young Indian bonded child laborers wait to be proc FILE - Young Indian bonded child laborers wait to be processed at a safe house after being rescued during a raid by workers from Bachpan Bachao Andolan, or Save the Childhood Movement, at a factory in New Delhi, India, June 11, 2013. FILE - Young Indian bonded child laborers wait to be processed at a safe house after being rescued during a raid by workers from Bachpan Bachao Andolan, or Save the Childhood Movement, at a factory in New Delhi, India, June 11, 2013.

"People are released physically but not really released from the burden of the debt, or the mental trauma they have undergone," said Umi Daniel, a migration expert at the Aide et Action International charity.

Many former slaves instinctively curl up in their beds, used to spending a couple of hours sleeping in a cramped space, Jhona told the Thomson Reuters Foundation.

While survivors of sex trafficking often receive help in shelter homes, rescued bonded laborers simply return to their villages and completely shut down.

"Very often there is no talk of the years spent in bondage," said Jhona, adding that workers often find it hard to tell her of their hopes for the future.

"They ask us how they can have aspirations, when even to eat or sleep they needed permission from their owners," she said.

"It is heartbreaking to see people with nil dreams and no aspirations, even for their children. They don't think a better future can exist and most refuse to talk about any of it for months."

No fear

Some rescued bonded laborers are coming together to lobby for their rights and share their stories.

Rukamana Deep says he finally "felt free" when he gave a lecture at the Odisha National Law University in April, describing how his family of four were trapped in a brick kiln.

Deep was able to tell his tale in detail, recounting his anger, despair and helplessness as they worked round the clock to make up to 1,000 bricks a day for 100 Indian rupees ($1.56).

"There was no fear that day," he told the Thomson Reuters Foundation in a telephone interview from his village in the eastern Indian state of Odisha. "I just wanted to tell my story."

Deep says his confidence comes from the fact that he knows he is not alone, after attending monthly meetings of a migrant bonded labor forum, Dadan Goti Shramik Surakshya Manch.

"We just talk about a lot of things, including the present challenges and the past problems," he said. "We understand each other and also create teams that immediately reach out to recently rescued workers. It's important for them to talk."

Daniel, of Aide et Action International, believes such forums are critical.

"It's a big step in their healing process," he said.