Social media has been awash with images of Elizabeth Nyalong Angong, age 17, on her wedding day. She is pictured in a sleeveless white lace wedding gown and veil and holds a white and pink bouquet. The look on her face is vacant.

The groom in the bright blue suit beside her is 50-year-old Kok Alat. Two weeks earlier, Alat came in as the highest bidder for Nyalong's hand in marriage and settled on an elaborate dowry with her parents.

Facebook failed to notice 

The family from Awerial in Eastern Lakes State had put their daughter up for auction, listing what they wanted in exchange for her hand in marriage. The post was taken down two weeks later, by which time the parents had settled with the highest bidder and the marriage was sealed.

At least five men placed bids. Alat offered over 500 cows, three top range Toyota Land Cruisers and 10,000 dollars in cash. The parents were pleased, and Nyalong and Alat – a local businessman reported to have more than half a dozen wives – were married in a traditional Dinka ceremony.

Images of the wedding went viral on social media and sparked widespread anger and condemnation across South Sudan and beyond. But there has been little immediate action to stop the marriage.

Call for stronger laws

Phillips Anyang, a human rights lawyer with Advocates Without Borders says the case highlights the problem of child marriage in the country.

"The auctioning that took place is a clear violation of her rights under the constitution, the child act and of course the obligation that we have ratified the South Sudan international instrument on the convention on the rights of the child," he told DW.

Human rights and women's groups described the auction of Nyalong as dehumanizing and denounced the commodification of women. South Sudan-based groups such as the National Alliance for Women Lawyers also called on the government to change laws in the interest of children and women.

The alliance says the incident violates the UN Convention on the Elimination of all forms of Discrimination Against Women and has Parliament to amend and strengthen laws governing the interests of children, especially girls, and women.

Last month, a nine-year-old girl who had allegedly been raped by a former Culture, Youth and Sports Minister of Fagak State was reported to have escaped child marriage. The man had colluded with her relatives to make her his wife, agreeing he would pay 10 cows and the equivalent of 3,500 dollars to them if he could take the child as his wife.

Politicians often wed children

In accordance with Dinka customs, men can marry underage girls. The girl's parents ultimately decide if he will make a good husband, with the means to care for their daughter.

"It is totally outrageous because this robs the girl of her freedom of choice­; that is the right to choose whoever she wants," says Robert Badri, who heads Badri and Associates, a non-governmental organization that campaigns against gender-based violence in South Sudan.

"It [the marriage of Nyalong and Alat] totally defeats the constitutional idea of marriage; it totally defeats the constitutional definition of family."

Child marriage in South Sudan is rarely condemned by authorities. The country's politicians and senior defense forces personnel are often the very men who marry children.

Badri says the war-torn country's transitional constitution and its Child Act of 2008 are too weak to prevent the practice. As it stands, the constitution does not define a minimum age for marriage in South Sudan. It simply states that any person of marriageable age can start a family.

"The case of Nyalong is extremely difficult in the sense that the constitution is not clear. Because for you to be able to take this matter to court you have to establish very clearly that such act contradicts our law clearly," says Badri.