China's foreign ministry spokeswoman, Hua Chunying, told a daily news briefing in Beijing that she was unaware of the report.
Two Canadians - former diplomat Michael Kovrig and businessman Michael Spavor - were detained after Canadian police arrested Huawei Technologies Co Ltd's chief financial officer, Meng Wanzhou, on Dec 1.
Canada's Global Affairs office told the National Post that they were aware of a detention but did not provide details and did not suggest a connection to Meng's detention.
The newspaper did not identify the third person to be detained but a source who had spoken to the individual's family told the newspaper that the individual was not a diplomat or an entrepreneur.
Canada's embassy in Beijing did not immediately respond to an emailed request for comment on the report.
The Canadian government has said that there is also no explicit link between Meng's arrest and the detentions of Kovrig and Spavor.
But Beijing-based Western diplomats and former Canadian diplomats have said they believe the detentions are a form of "tit-for-tat" reprisal by China, in response to Meng's arrest.
U.S. prosecutors accuse Meng of misleading multinational banks about Iran-linked transactions, putting the banks at risk of violating U.S. sanctions.
Meng, who is the daughter of Huawei’s founder, has said she is innocent. She has been released on bail.
China has repeatedly called for Canada to correct its mistake and to release Meng or face unspecified consequences.
Both Kovrig and Spavor are being investigated on suspicion of endangering China's state security, the Chinese government has said. (Reporting by Ben Blanchard, Philip Wen and Christian Shepherd Editing by Robert Birsel)
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)