Huseyincan Celil, an ethnic Uyghur, was arrested in Uzbekistan in March during a family visit. Celil faces possible execution if convicted in China.
Beijing accuses him of involvement in a 2000 attack on a state delegation in China's western Xinjiang Province, the home region of Turkic-speaking Uyghurs.
A pro-government Uzbek website, press-uz.info, quotes an unidentified security official as saying Celil is also wanted in Kyrgyzstan over the murder of Uyghur community leader Nigmat Bazakov six years ago.
One man (Otabek Ahadov) has been sentenced to death and another three to lengthy jail terms in Kyrgyzstan over Bazakov’s murder.
The Uzbek authorities insist Celil's real name is Guler Dilaver and that he is a Turkish citizen.
Canada is pressing Beijing to reveal what it has done with Celil.