Story highlights CNN team finds a man at "unofficial" displaced camp willing to provide children to be "fostered"

He says he can't take money for them, but eventually demands $500 for two girls

CNN's Nima Elbagir has been named Specialist Journalist of the Year by the Royal Television Society, in recognition of her work highlighting the human rights plight of children and young people. In this piece from March 2015, Elbagir, producer Lillian Leposo and cameraman Fabien Muhire filed this exclusive report on claims children were being bought and sold in Nigeria.

(CNN) "It really depends what you want. Boy? Girl? Young? Old?"

The man on the phone was offering us young children with the casualness of a market trader. After a week of back and forth phone calls, his initial caginess had given way to greed. He'd heard my foreign accent and clearly decided I would pay more than the domestic rate.

"We can get," he said.

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We'd been put in touch with the man through a contact on the ground. We were told he was one of the men running this "unofficial" displaced camp -- one of the many that has mushroomed in the town of Yola as the influx of people fleeing Boko Haram has grown beyond the capacity of the official camps.

It had all been heartbreakingly simple. We'd asked who had children available to "foster" -- a catch-all code word designed to conceal the true intent of those offering up the orphaned children. The man on the phone was the end result of those inquiries.

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