An auction was discussed on the social media platform for a girl aged 16 or 17 in South Sudan that sought payment for her hand in marriage.
Facebook said the post was taken down as soon as the company learned of it, but that wasn't until after the girl involved was married.
According to children's rights organization Plan International
, the girl was bid on by five men, some of whom were reportedly high-ranking South Sudanese government officials.
Activists are concerned that this auction -- for which the father reportedly received 500 cows, three cars and $10,000 in exchange for his daughter -- could inspire other families to use social media sites to receive larger payments.
Plan International's country director in South Sudan, George Otim, said: "That a girl could be sold for marriage on the world's biggest social networking site in this day and age is beyond belief."
He added: "This barbaric use of technology is reminiscent of latter-day slave markets."
'It just went viral'
South Sudanese human rights lawyer Phillips Ngong told CNN the auction took place in person and not on Facebook.
Ngong said the family had no intention of posting to Facebook, but the dowry amount pledged for her was higher than usual and generated a lot of discussion among Facebook members.
"In South Sudan, Facebook and social media is a brand new thing. Someone just took a picture. And it just went viral," he added.
Though Facebook said the post was taken down on November 9, posts discussing the dowry were still live on Friday, November 23.
These posts discussed the price being offered for the girl by the highest bidder, as well as how much Facebook users would offer for her. CNN has flagged these two live posts to Facebook, which has yet to issue comment.