A Chinese bookstore draped a one metre-long metal chain over a table flanked by books on feminism last week, in an unusually public contribution to outrage over a video showing a woman shackled by her neck in a village.

The video, which came to light in late January, was seen by millions of people online and caused an outcry about the treatment of women in China and less discussed issues such as the trafficking of brides.

Under pressure from social media users, authorities in the province of Jiangsu and the county of Feng where the woman lives eventually detained three people including her husband.

The chain at the bookstore, in the city of Hangzhou, near Shanghai, was accompanied by a banner that read: "Books you should read about Feng county," videos posted on Chinese social media platforms showed. Reuters confirmed the display with the bookshop.

Next to the chain were books on male dominance in society such as Rebecca Sonit's "Men Explain Things to Me" and Pierre Bourdieu's "Masculine Domination".

After a few days, the bookstore had removed the chain by Sunday night, images posted online showed and a clerk at the bookstore said.

The store wanted to have a female theme, but later took it down as "it was quite a controversial topic," said the clerk, who spoke to Reuters by telephone but declined to be named because of the sensitivity of the matter.

China says it seeks to empower women and protect their rights but restricts activities and discourse - online or offline - that it feels could agitate social order or suggest defiance of its authority.

Reuters could not immediately establish what had happened to the woman since the outcry.

The original video showed her chained by the neck in the kitchen of a shack, without a coat despite winter temperatures. The video blogger who filmed her said she had eight children, unusual in China which restricts the number of children families can have.

Authorities have given conflicting accounts of what led to her being shackled. Officials' initial reaction was to justify her situation by saying she was mentally unstable.

In the face of online anger at this explanation, authorities investigated further and concluded she had been trafficked for marriage. Two people were detained for people trafficking, and her husband was held for illegal imprisonment.

Forced marriage is a phenomenon in some parts of China where there are less women than men, possibly because of an earlier one child policy, which led some families to sometimes abort girl children. The practice has previously been documented in villages in Jiangsu.