Former Canadian diplomat Michael Kovrig (L) and entrepreneur Michael Spavor (T) were taken into custody in China on Monday and that they are being handled separately (Photo: AP)

Foreign Ministry spokesman Lu Kang told a press conference on Thursday that Kovrig has been on the radar of Beijing's National Security Bureau while Spavor is being investigated by the National Security Bureau of Dandong city in Liaoning province.

Lu said both bureaus had notified the Canadian embassy in Beijing and the legitimate rights and interests of the two Canadians are being respected.

The detentions were carried out a week after Canadian authorities arrested Meng Wanzhou, Huawei's Chief Financial Officer, at the request of the US.

China asked Canada to correct the mistake and immediately release Ms. Meng, or face grave consequences.