Canadian Prime Minister Justin Trudeau listens to a question during a news conference in Ottawa on Dec. 19. (Adrian Wyld/AP)

A third Canadian national has been detained in China over a visa violation, the Chinese government said Thursday, distancing the case from two other arrests seen as political chips in an escalating row between Beijing and Ottawa.

Sarah McIver, a teacher from Alberta province, is currently being held as “administrative punishment” for working illegally in China, Foreign Ministry spokeswoman Hua Chunying said. She added that McIver’s offense differed in nature from those of Michael Kovrig and Michael Spavor, two Canadians who were detained this month on national security grounds.

McIver’s detention, first reported this week by Canada’s National Post, immediately sparked fears in Ottawa that she had become a third Canadian citizen to be effectively held hostage by Beijing in a spiraling tussle over Chinese business executive Meng Wanzhou, the Huawei Technologies’ chief financial officer who is wanted by U.S. law enforcement and was arrested in the Vancouver airport on Dec. 1 during a layover.

Ten days after Meng’s arrest, Chinese state security agents detained Kovrig, a former Canadian diplomat and analyst for the International Crisis Group based in Beijing, and Spavor, a consultant who runs cultural exchanges in North Korea.

Chinese authorities said the men violated laws regulating nongovernmental organizations, but a letter from the Chinese ambassador to Canada published in a national Canadian newspaper compounded the sense that the arrests were a tit-for-tat reprisal for Meng’s seizure.

The National Post reported Wednesday that people close to the case expect McIver to be returned to Canada in the coming weeks, possibly by the new year. 

Canadian Prime Minister Justin Trudeau also downplayed the link between the three cases, telling reporters that the third detention did not “seem to fit the pattern” of Kovrig’s and Spavor’s arrests.

Administrative detentions lasting several days or a week are seen in China as relatively light punishments and can be levied by local police for matters ranging from visa violations and minor political offenses to drug infractions and bar fights. For years, Chinese immigration authorities have more or less turned a blind eye to foreigners working in the country on tourist visas.

But the souring political climate has heightened concerns for Canadians living in China, with the Canadian government warning its diplomats and embassy staff to take extra precautions in the country.

China’s government has threatened “severe consequences” for Canada if it does not free Meng, who is currently out on bail in Vancouver pending a formal Canadian decision on whether to send her to the United States. Meng, the daughter of Huawei founder Ren Zhengfei, is wanted by U.S. authorities for alleged fraud related to Huawei’s business dealings with Iran.

Canada has flatly denied that Meng’s arrest was politically motivated, saying it was merely carrying out its obligations as an extradition treaty signatory with the United States.

But President Trump cast the dispute in a political light last week, telling Reuters in an interview that he could intervene in Meng’s extradition case if China offers trade concessions.