KCBS_740BERLIN (AP) — German police say a 28-year-old man has admitted listing his infant daughter for sale on eBay but maintains that it was meant as a joke.

The 40-day-old girl was listed on the internet auction site last week at a price of 5,000 euros ($5,500). Police in the western city of Duisburg raided the parents’ apartment and put the girl into care. They opened an investigation on suspicion of human trafficking.

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Police said Monday that the father went to authorities on Friday and admitted posting the offer. He gave investigators a cellphone he used to do so.

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Police have described the family as refugees, without giving further details.

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