BEIJING — Chinese authorities have refused to permit Canadian diplomats to attend a trial of a Canadian-born tycoon who vanished from Hong Kong five year ago.

Xiao Jianhua, who was last seen in a Hong Kong hotel on January 2017, is believed to have been taken to China by Chinese authorities. He has not been confirmed by the government as to whether or not he was taken into custody.

Get the NBC News app to get breaking news and political updates

The Canadian government stated that Xiao would be facing trial on Monday, but did not specify if or where. The Canadian government did not provide details about possible charges.

“Canada requested several times to be present at the trial proceedings. “Chinese authorities denied our attendance,” stated a Canadian government statement.

Xiao, founder of Tomorrow Group, was killed in a flurry criminal prosecutions of Chinese businessmen accused of misconduct.

This sparked fears that the ruling Communist Party could be abducting people from the mainland. Hong Kong had at the time banned Chinese police officers from operating in the former British colony. It has a separate legal structure.

Beijing has increased its control over Hong Kong since then, causing complaints that it is violating the autonomy promised in 1997 when the territory was returned to China. In 2020, the ruling party passed a national security law and jailed pro-democracy activists.