BEIJING, Mar 31, 2001 -- (Agence France Presse) China's detention of U.S. academic Li Shaomin sends a chilling message to foreign researchers and international investors, the lobby group Human Rights Watch said Saturday.

Li, a U.S. citizen who works as a business lecturer in Hong Kong, has been in detention in China since February 25 on unspecified charges. His arrest, revealed on Friday by the U.S. embassy, came two weeks after Gao Zhan, a scholar who now lives in the U.S., was arrested for alleged spying.

"This appears to be another case of a foreign academic detained in China because his research or views are contrary to state policy," said Sidney Jones, Asia director of Human Rights Watch.

"We're asking that the charges against Professor Li be made known, and that he be immediately and unconditionally released unless there is clear evidence that he has committed a non-political offense."

HRW said China's action against Li may have been influenced by the fact that his father, Li Honglin, is a well known advocate of political reform and former political prisoner in China.

"The chilling effect of Li's detention on the international academic and business communities is all the greater, coming as it does on the heels of the detention of Gao Zhan," said Jones.

HRW has also called for the immediate release of Gao, who is awaiting US citizenship. Her husband, Xue Donghua, who was detained with her but later released, became a U.S. citizen on Friday.

The couple's five-year-old son was separated from them for 26 days during the detention, which the U.S. embassy was not notified of.

"These two detentions, along with other widespread abuses of human rights, raise serious questions about China's willingness to respect basic international norms," Jones noted.

In October 1998, China signed the International Covenant on Civil and Political Rights which specifically bars arbitrary detention. But Beijing has yet to ratify the treaty. ((c) 2001 Agence France Presse)