A still image taken from video shows a housekeeper wringing water from a kitchen cloth into a pot used to prepare a herbal drink for her employer in Hanoi.
The woman, 58, was hired by a family in Ngoc Thuy Ward, Long Bien District through an agency in April.
She reportedly boiled perilla leaves without washing them and used a cleaning rag to mop up spilled water, which she then wrung into the pot, according to footage reviewed by the homeowner.
Ngoc Thuy Ward police said they had recorded the incident and were reviewing it for possible legal action.
The housekeeper admitted the act during questioning and said it was "done in haste and unintentional," police said.
The master filed a complaint after suffering stomach pain and reviewing surveillance footage on May 11.
The case remains under investigation.
