Hyacinth Orikara, a doctor at the Heda clinic in Aba in the southeastern state of Abia, was arrested along with the girls during a raid last weekend which followed a tip-off that infants were being "farmed" and sold, police said on Thursday. "He was arrested along with 32 pregnant teenage girls found in his clinic," Abia police spokesman Geoffery Ogbonna said.

Orikara told police the clinic was an adoption agency meant to help teenagers with unwanted pregnancies and that the babies were usually handed over to the social welfare office. But police said he could not mention any specific office.

The girls, aged between 15 and 17, told police they were offered between 25,000 and 30,000 naira ($160-190) for their babies, depending on the sex.