A 23-year-old man who married an 11-year-old girl has been detained in the town of Mali Yemberin, in Guinea's Fouta Djallon region.
The wedding took place earlier this week, but after social media outrage at the union, the man returned the girl to her parents.
The groom's parents, the girl's parents and the imam who officiated the marriage are also being questioned by the police in the highland region of the mainly Muslim West African nation.
"We have many little girls that are being forced into marriages especially in the region of Labe in Fouta," said Hadja Idrissa Bah, chairwoman of Young Leaders Club - an organisation fighting against forced marriage, marital rape and genital mutilation.
"In fact the younger sister of the man who has been arrested and who is only 14 years old is also being prepared by her parents to get married," she added.
Child marriage is a growing phenomenon in the country.
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