GENEVA (AP) — A group of independent experts appointed by the U.N.'s main human rights body say China's government has wrongly held three activists and is calling for them to be released and compensated.

The five-member Working Group on Arbitrary Detention, in an opinion reached in August but not yet made public, says detentions of Hu Shigen, Xie Yang and Zhou Shifeng violate the International Convention on Human Rights.

Britain's Guardian first reported the information, having obtained a copy of the opinion which has been presented to China's government and concerned parties but is still undergoing fine-tuning.

U.N. staffers confirmed the opinion of the group to The Associated Press on Friday.

The group is comprised of five independent experts appointed by the Human Rights Council, a 47-member, U.N.-backed body that currently includes China.