Huawei’s equipment is used in mobile phone and internet networks around the world. But American officials have for years considered the company to be vulnerable to efforts by Beijing to spy on Americans or sabotage their communication systems.

Huawei denies that it operates as an extension of Beijing. Still, as the company has grown to become the world’s top supplier of telecommunications gear, the United States government has worked to discourage American mobile carriers and consumers from buying its equipment. Washington has shared its security concerns with allied governments in Europe and elsewhere.

On Dec. 1, Meng Wanzhou, Huawei’s chief financial officer, was arrested in Canada at the request of the United States. American investigators have accused her of deceiving financial institutions about Huawei’s business in Iran, causing them to inadvertently violate United States sanctions. The Canadian legal authorities have not yet decided whether Ms. Meng will be extradited to the United States.

Diplomatic tensions between China and Canada jumped after Ms. Meng’s arrest, with Beijing detaining several Canadians in what were seen as tit-for-tat arrests. Among those still being held in China are Michael Kovrig, an experienced diplomat and Sinophile who had spent years investigating sensitive subjects like the human rights of minority groups in China; and Michael Spavor, an entrepreneur with high-level contacts in North Korea.

The second person arrested by the Polish authorities this past week was an employee of Orange, the French telecommunications company. Orange’s office was raided, and the employee’s belongings were seized. Polish officials did not offer more details about what the two men were accused of, but said that they would be held for three months while the investigation continued.