New Taipei, Aug. 17 (CNA) A police officer in New Taipei is facing possible criminal charges after an incident Monday in which he is alleged to have arbitrarily shackled and detained a migrant caregiver.

The allegations of police abuse came to light Monday evening, after Huang Tzu-hua (黃姿華), a representative of a domestic caregivers' union based in Taoyuan, posted an account of the episode on her Facebook page.

According to Huang, the incident began when the woman ‒ a domestic caregiver for an elderly Taiwanese woman in the city's Sanchong District ‒ went downstairs to throw out the garbage on Monday.

As she stood outside talking on the phone with her friend, she was approached by a policeman, who shouted at her and demanded to see her alien resident certificate (ARC), Huang said, adding "who takes their ID to throw out the trash?"

The officer, who apparently assumed the woman was a runaway migrant worker, first handcuffed her to a chair at a nearby 7-Eleven store.

He then drove her to Zhongxing Bridge Police Station, where she was placed in leg shackles and interrogated, Huang said.

After police determined that the caregiver was working in Taiwan legally, they agreed to release her, but made no offer to return her to the place where she had been arrested.

As the woman had just gone to throw out the garbage, she did not have any money on her to take a taxi, and was thus left to find her way home using Google Maps, according to Huang.

In the post, Huang said the woman was distressed not only by her treatment but also about being away for so long from the elderly woman she is responsible for caring for.

Huang's post about the incident Monday evening was shared over 2,500 times, with several comments criticizing the police for acting like they "run the country."

Lin Ku-ting (林故廷), Sanchong Precinct police chief, said he was "furious" upon learning of the incident, and had ordered an overnight investigation to find out what had happened.

He said the officer in question, surnamed Hsieh (謝), defended his actions to investigators, saying he had approached the woman because she was "looking around" suspiciously and had a "strange expression."

Hsieh claimed he and the woman got into an argument because of a "language barrier," and said he decided to bring her to the police station to confirm her identity, Lin said.

The department concluded, however, that Hsieh's actions were a breach of police conduct, and it has asked the New Taipei City Prosecutors Office to investigate him for possible offenses against personal liberty under the Criminal Code, the police chief said.

According to Lin, Hsieh will be transferred away from front-line police duty pending a decision by prosecutors on whether or not to press charges. "The consequences will be severe" if he is found liable, he said.

Lin said he personally visited the caregiver on Monday night to apologize, and to explain how the department was planning to follow up on the incident.