A video footage shows a locksmith breaking open the lock on 37-year-old Hoang Phuong Lan's door at the Ehome 4 apartment complex in Thuan An Town, and officers entering the house and marching her out, arms pinned behind her back.

Outside she had samples taken for Covid-19 testing.

Her son can be heard crying and Lan can be heard saying she cannot go out for testing since she was "working".

Vo Thanh Quan, secretary of the Vinh Phu Ward Party Committee, said two Covid cases had been detected in the apartment block, but Lan refused to test.

She locked her door and refused to come out for testing when authorities tried to persuade her, he said.

She tested negative.

Lan said she had told authorities her family members had been staying at home for long and tested themselves already.

They had not been in contact with anyone else, and did not want to go out to get tested, she said.

She claimed she had not heard the announcement that two people in the apartment block had Covid.

"Breaking down my door and incapacitating me was wrong. A few days ago they forcibly entered my apartment to take samples for Covid-19 testing."

HCMC is conducting Covid-19 mass screening and people can be tested multiple times every several days, depending on the infection risk level of their areas.

An investigation is being carried out into the lawfulness of authorities breaking into Lan's apartment.

It is not known why she was forcibly taken out instead of being sampled inside her home.

Binh Duong has had over 200,000 cases and 1,900 deaths so far.