The woman seen in a viral clip refusing to don a mask while at Marina Bay Sands (MBS) on Saturday is already facing a criminal charge over a similar offence allegedly committed last year.

According to court documents obtained by The Straits Times yesterday, Phoon Chiu Yoke allegedly failed to wear a mask over her nose and mouth "at all times" at Newton Hawker Centre between 7.20pm and 8pm on May 8 last year.

The 53-year-old was charged with an offence under the Covid-19 (Temporary Measures) Act.

She was accused of committing the offence during the circuit breaker period imposed between April 7 and June 1 last year to curb the spread of Covid-19.

Phoon is contesting the charge and the trial will take place next Monday.

She made the headlines this month after a video showed her arguing with a safe distancing ambassador (SDA) at MBS.

In the clip, an SDA can be seen trying to convince her to put on a mask.

Phoon questions the SDA on whether she has a "badge".

She is heard saying: "If you have no badge, why are you asking me to do something? Who are you representing?"

When the SDA replies that she represents MBS, Phoon says: "That's what you say. I can say that I'm a police (officer)."

At the end of the clip, Phoon can be seen clutching a mask which she slides into her pocket.

In an earlier statement, police said they received a call about the incident at around 5.15pm on Saturday.

Phoon is believed to be involved in other similar instances where she was seen in various buildings and establishments without a mask on.

There are at least two other videos circulating, showing her in public places without a mask on.

One of the videos was supposedly taken at VivoCity in February this year, while the other was at Clarke Quay Central in December last year.

First-time offenders who breach laws under the Covid-19 (Temporary Measures) Act can be jailed for up to six months and fined up to $10,000.

Repeat offenders can be jailed for up to a year and fined up to $20,000.