He had just parked his car and was getting ready for work when he noticed a commotion around a minibus two lots away.
Two police officers were at the bus, and a woman was taking photos of the vehicle on her mobile phone.
Mr Phillip Ngeow, 54, then noticed a little girl inside the bus. The bus doors were locked, the engine was off and she was trapped.
Despite this, she appeared calm.
"The girl was wearing a blue chequered uniform and wasn't crying. She must have been too young to understand anything," Mr Ngeow, the manager of an electronics shop, told The New Paper.
The incident happened at the open-air carpark at Block 503, Bishan Street 11, on Tuesday morning.
According to Chinese daily Lianhe Wanbao, it was speculated that the school bus driver had already dropped off the rest of the children on board at a childcare centre or kindergarten.
But he did not notice the sleeping girl in the bus, and had gone to park the minibus before presumably going for breakfast.
The pre-schooler had allegedly been left in the bus for about two hours.
A helper at a coffee shop in Block 503, Ms Liu, 51, told Lianhe Wanbao that she had seen the bus parked there as early as 9am, but only found out later that there was a girl inside.
Mr Wilson Ong, 41, an employee at Mr Ngeow's shop, told TNP that he noticed policemen asking around at the coffee shop for the driver of the school bus, and if there were any childcare centres in the vicinity.
Mr Ong also described vividly in Mandarin the sight of the girl in the bus: "She was seated just behind the driver's seat and there was condensation on the inside of the windows with her finger marks on it. "It meant she must have been inside for some time."
The Singapore Civil Defence Force confirmed that it was alerted at 10.43am and sent a fire engine, two fire bikes and an ambulance.
A spokesman said a cutter was used to cut through the vehicle's glass and a three-year-old girl was rescued unharmed. Her parents did not want her taken to hospital in an ambulance.
According to Mr Ng Kim Hock, a bus company owner, such incidents should not happen.
"For kindergarten and childcare centres, it is compulsory to have a bus attendant to make sure all the children have alighted," said Mr Ng, 52.
This article was first published on July 4, 2014.
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