A Chinese court awarded damages to the mother of a rape victim after she was sent to a labour camp for demanding her daughter's attackers be punished, a spokesman said.

Tang Hui, who became a figurehead for critics of the "re-education through labour" system after she was condemned to 18 months in a camp, won a total of $430 on Monday following an appeal, a court spokesman told AFP news agency.

The court in Changsha, the capital of the central province of Hunan, awarded compensation on the grounds that local authorities had violated Tang's personal freedom and caused her psychological damage, the spokesman said.

But it rejected Tang's demand that the police who sentenced her write a formal apology, because the "relevant people had apologised in court", he added.

Tang was released last August after just over a week in a labour camp following a public outcry over her case, which was given unusual prominence in state-run media and prompted speculation that the system would be abolished.

The compensation award comes as a surprise after Tang lost her initial case. She herself had estimated the chance of success in her appeal as a "remote possibility".

Tang's daughter, 11 at the time, was kidnapped, raped and forced into prostitution in 2006, prompting Tang to seek to bring to justice the abductors and the police she says protected them.