Police sources say as many as 4000 children are being trafficked out every month for work.
It is 6 am on a cold morning in Gaya, 120 kms from Bihar's capital city of Patna. The train station here is in quantum activity mode, a ready store of passengers streaming through platforms, settling into trains.
In the compartment of a train headed to Jaipur are two brothers. They are unaccompanied; the older appears to be about 10. Activist Manoj Kumar asks them where they are headed. They say they are traveling to Jaipur. Both say they have been there before and were deposited in the compartment by a middleman who had organized jobs for them at an embroidery factory. They are too distraught to explain much more about their parents and are taken to a welfare home where they will be looked after till officials are able to contact their family.
Gaya is an important stop for trains headed through the state. In the past few years, activists and the police say, this has turned it into a major drop-off point for child labour.
Mr Kumar spots a couple with six children on a platform. They say they are taking them on vacation to Jaipur. Three, they say, are their own children; the other three are relatives. The police that is accompanying Mr Kumar talks to them at length; they are then arrested on charges of child trafficking. Three of the children are from a village in Nalanda, close to the couple's home, and were being taken to work in zari factories in exchange for money given to their parents.
Official child trafficking figures for 2014 for Bihar are not available, but police sources say as many as 4000 children are being trafficked out every month for work.
The supply lines are coming from villages like Atiya in Bodh Gaya, where Tilak Manjhi, a marginal farmer with a meagre income and a family of six to support, says he sent his son to Himachal Pradesh nine years ago, with a relative, who promised in return to send Rs 300 per month. Since six-year-old Jitu left home, there has been no contact with his family. Manjhi's son and relative remain untraced.
The Bihar government told the Supreme Court in October 2014 that nearly 2,000 children who went missing in the last few years from the state have been recovered, while at least 600 were still untraced.
Alok Kumar Singh, Deputy Superintendent of Police at Gaya, says "This is not a policing failure. We try and do as well as we can. Most of these traffickers almost hypnotize the families into letting their children go".
Last week, the Hyderabad police, in a raid to locate terror suspects, stumbled into a house where 200 children from Bihar were working on making bangles. Many of them had left home months ago.
As they are returned to their families in Gaya, many of the trains departing the same station are carrying others like them, scared, poor and sold into a bleak future.