By Amarnath Tewary Patna, Bihar

Chunam Kumari with her poster

An inquiry has been ordered in India's Bihar state into reports that a young girl who appears on anti-child labour posters is working at a food stall.

Chief Minister Nitish Kumar has asked the state home commissioner to conduct the investigation.

Eight-year-old Chunam Kumari's photo was used by Unicef in an awareness campaign about child labour in the state, one of India's poorest.

India recently banned children below 14 from working in homes or restaurants.

Mr Kumar announced the inquiry at Patna airport as he was leaving for Delhi.

He told journalists that he had also asked the state welfare department to find out ways to rehabilitate the girl.

Long hours

Although Chunam Kumari's photograph was used by Unicef on its posters, she continues to work 12 hours a day at her father's ramshackle roadside food stall in the capital, Patna, cleaning creaky wooden tables, washing utensils and serving up cheap meals.

Unicef says it used the photograph in its campaign to raise awareness about child labour, but it says Chunam is not a Unicef brand ambassador.

Unicef says it has written permission from Chunam's father to use the picture.

Chunam's father, Baleshwar Das, insists he never signed any documents and says his signature may have been forged.

The chief minister said the government would also investigate the allegations of forgery.

India has more than 12.6 million child workers, many of whom are employed in the food and hospitality sector.

Many parents say crippling poverty forces them to send their children, sometimes as young as five or six, to work in other people's homes or in factories.