Three officials who approved and conducted a controversial test of genetically modified rice on school children in Central China's Hunan province have been sacked, authorities said on Thursday.

The officials were punished for "violating relevant regulations, scientific ethics and academic integrity", according to a statement released by the Chinese Center for Disease Control and Prevention, the Zhejiang Academy of Medical Sciences and Hunan Provincial Center for Disease Control and Prevention.

The officials include Yin Shi'an from China CDC, Wang Yin from Zhejiang Academy of Medical Sciences and Hu Yuming from Hunan provincial CDC.

The Ministry of Health had previously ordered China CDC to investigate whether dozens of children in Hunan were used in 2008 as test subjects in a US-China joint research project that included GM food Golden Rice.

Greenpeace exposed the details of the controversial test in late August, saying that the joint research involved feeding Golden Rice, which is genetically modified to be rich in beta carotene, to 25 children aged 6 to 8 in Hunan.

It cited a paper published in the August edition of The American Journal of Clinical Nutrition.

The paper claimed that Golden Rice is effective in providing vitamin A to children.

The research, which was approved by the National Institutes of Health in the United States in December 2002, was led by Tang Guangwen, director of the Carotenoid and Health Laboratory of Tufts University in the US. It was intended to explore ways to prevent deficiency of vitamin A in children.

Tang conducted the research in cooperation with Yin Shi'an and Wang Yin.

In 2008, the test was conducted on 80 students in Hengnan county in Hengyang of Hunan province, with 25 of them fed 60 grams of Golden Rice on June 2.

The research team had informed the parents of the children about the experiment but withheld that GM rice would be used.

Hengyang government will give 80,000 yuan ($12,800) to each of the 25 families whose children consumed the rice as compensation for participating in the project, the Oriental Morning Post reported on Thursday.