The man was wearing a surgical mask, covering part of his face.
Thinking he was a customer, Ms Farfalla Vi thought nothing of it. She greeted him and asked if he had an appointment.
Instead of answering, he whipped out a knife.
Said Ms Vi, 40, a customer service officer at Rose Spa at Block 531, Ang Mo Kio Avenue 10: "He grabbed my right arm and my mind went blank.
"I was prepared to give him whatever he wanted, hoping he would not hurt me."
The masked man held the knife to her back and pushed her towards the cash register.
Said Ms Vi, a Thai national: "He spoke in Mandarin so I couldn't understand, but I could tell he was asking me to open the cash register quickly."
The man took out a plastic bag from his pocket and demanded she empty the cash register.
Ms Vi did as she was told, and the man left with about $850 cash.
The robbery took place on Wednesday and a police report was made at about 1.20pm.
The spa is in a row of shops in the busy neighbourhood.
Though her mind was a blank for a while, Ms Vi said she tried to stall the robber.
"I even tried to take the money out slowly, hoping my colleagues would come out and help," she said.
Unfortunately, her seven colleagues were in the spa rooms and did not suspect anything. There were no customers at that time.
The robber became impatient and started raising his voice.
"He was shouting 'faster! faster!' in Mandarin. After that, he snatched the plastic bag which contained the money and walked out of the shop swiftly," said Ms Vi, who alerted her colleagues.
They then ran out of the shop screaming "robbery!', alerting other shopkeepers.
Mr Vincent Sim, 55, owner of Broadway Florist opposite the spa, was sitting outside his shop when he heard the commotion.
He said: "I saw five to six women in bright pink uniform yelling 'robbery! robbery!' in Mandarin.
"I didn't know what was happening. When some of them told me about the incident, I was shocked because I didn't see anyone suspicious running out of the shop the entire morning."
A staff member at Hockhua Tonic, beside Rose Spa, said she caught a glimpse of the man when he entered the spa.
She said: "When he was walking into the shop, he looked like any other customer. I didn't suspect anything so I just carried on with my work."
Following the incident, Rose Spa closed at 3pm.
The spa's owner, who only wanted to be known as Ms Rebecca, said her staff were shaken by the experience and worried about turning up for work yesterday.
"I tried to comfort the girls by taking them out to eat and helping them take their mind off things," she said.
Despite this, Ms Vi said she was still worried.
She told The New Paper yesterday: "I'm still recovering from the shock. I was so scared to come to work.
"I never thought this kind of thing will happen in Singapore. I normally see this on television, not in real life."
The police said a 25-year-old suspect was arrested yesterday within 12 hours of the report being lodged.
He is expected to be charged today with armed robbery.
If convicted, he could be jailed up to 14 years and be given not less than 12 strokes of the cane.
1. The robber holds the knife at Ms Vi's back and pushes her towards teh cash register
2. He takes out plastic bag and demands she empty the register. He flees with $850.
This article was first published on January 22, 2016.
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