Mr Dennis Tay, 53, and his wife were about to pay for their groceries at the checkout counter at Tampines Giant Hypermarket when a woman pushed past them.
The couple's quiet morning was about to take a strange turn.
The woman, who was screaming, then climbed on top of the counter, stood above the moving conveyer belt and shouted for help.
Mr Tay, a businessman, told The New Paper: "She stood right in front of me. At first, I thought she had stolen something because I saw someone chasing her.
"She was screaming and calling for help and said that someone wanted to kill her. She also shouted for someone to call the police."
He said he had seen her running towards him. She was being chased by another woman who he believed was her friend.
"Her friend was shouting, 'Who do you think you are?' I'm not sure what happened earlier, but she screamed and shouted when her friend tried to hold her hand and get her down.
"I was concerned that she might grab stuff and hurl them at the people around her."
The woman, who looked to be in her late 20s, stood on the counter for almost an hour shouting and screaming. Her actions attracted a crowd of more than 20 curious onlookers.
A 22-year-old salesgirl who gave her name only as Miss Koh said: "Her friend had chased her from inside (the supermarket) and shouted for someone to stop her from running away. I think a customer tried to stop the woman and that's when she climbed up on the counter."
This reporter saw the woman drinking from a green tea bottle as she stood on the counter. Between bouts of screaming, she seemed calm and busied herself with her mobile phone. But she became agitated when anyone approached her.
According to Mr Tay and other witnesses, the woman spat her drink at security guards who had tried to coax her off the counter.
About seven of her colleagues from semiconductor manufacturer GlobalFoundries arrived almost 30 minutes into the stand-off and said they were concerned for her well-being. They said they did not know what had happened earlier and declined to comment further.
The friend who was seen chasing the woman was visibly distressed and in tears. She is also a colleague of the woman.
Someone was seen handing the woman a mobile phone and she appeared to talk into it while holding it away from her face before suddenly throwing it to the ground. Her colleagues were taken aback.
Police said that they received a call for public assistance at 1.28pm. A 24-year-old woman was later arrested under the Mental Health Act.
Under the law, the police can arrest a person who is reported to be mentally unsound and believed to be of danger to herself or others.
A Giant spokesman said its ground staff had reported that a woman queuing at the cashier counter with two of her colleagues "started behaving strangely and got up on the counter".
Security guards and staff members had tried to calm her down but were unsuccessful.
Eventually, one of her colleagues managed to persuade her to get down from the counter. She then spoke to the police while her colleagues stood a distance away.
About 10 minutes later, a police officer was overheard telling the woman that she had been given many chances but had not listened. She was then handcuffed and taken away.
When TNP called GlobalFoundries' Singapore office in Tampines yesterday, no one answered.
This article was first published on Sept 22, 2015.
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