He was on his way to drop off two passengers when a black car sped past his taxi along Thomson Road and honked at him.
Immediately, ComfortDelGro cabby Weng Dianlai kept an eye on the car as he thought the driver was behaving strangely.
As they drove onto Marymount Road, the black car, which was on the rightmost of three lanes, suddenly veered left and crashed into a tree.
Mr Weng stopped his taxi and rushed to the driver's aid with his two passengers.
Seeing that the car had caught fire, he grabbed a fire extinguisher from the boot of his taxi and tried to extinguish the flames.
In the meantime, his two male passengers pulled the driver out - just before the car was engulfed by fire.
The accident happened at around 4.20am last Thursday on Marymount Road in the direction of Ang Mo Kio Avenue 6.
On Monday, the driver, Mr Raymond Ang, thanked the cabby who saved his life via a Facebook post.
In an interview with The New Paper yesterday, Mr Weng, 58, a cabby of about 20 years, played down his selfless act, insisting that he was merely helping a person in need.
"It was nothing. I was just passing by and helping out. I don't want to be a hero," he said in Mandarin with a chuckle.
Recounting the incident, Mr Weng, a relief driver, described how he was about to head home at about 4am on Thursday when two men flagged down his taxi in Balestier. He decided to take them to their destination in Shunfu.
As he was driving along Thomson Road, Mr Ang's black car sped past him and honked at him.
That was when Mr Weng noticed that Mr Ang's driving seemed erratic.
When Mr Weng pulled up beside the car at a traffic light, he stole a glance at the driver, but did not notice anything unusual.
The black car sped off as soon as the traffic light turned green in their favour.
Mr Weng said he kept at a distance behind the car.
As they drove onto a bend on Marymount Road near Mount Alvernia Hospital, the black car suddenly swerved left across three lanes, mounted the kerb, hit a wall of the hospital's carpark and crashed into a tree.
A former tow truck driver for three years, Mr Weng said he has seen many traffic accidents, but this one looked especially serious.
"The whole front portion of the car was dented and smashed in. My first thought was of the driver.
"When I saw there was thick, black smoke coming from the car engine, I knew it was not good," he said.
When asked if he was concerned for his own safety, he said: "I was not afraid. There was no time to think about being afraid because we had to help him."
He said his passengers were initially reluctant to pull the driver out and said they should wait for the ambulance.
But the fire got bigger so he instructed them to quickly pull the unconscious driver out. The car was engulfed in flames soon after.
Mr Weng said he tried waking the driver by shaking him but he did not respond.
Police and Singapore Civil Defence Force officers arrived at the scene and firefighters put out the flames using a water jet.
But as Mr Weng's passengers needed to get home, the cabby and the two men left the scene soon after giving their statements.
Mr Weng said he did not even tell his wife about the incident until yesterday morning as he felt it was "normal" to have helped someone in need.
"She just said: 'Orh'.
"As for my children, they can read about it in the newspapers," said Mr Weng, who has two daughters and a son.
He also said he was glad to hear that the driver had recovered from the accident.
When asked if he would meet up with Mr Ang, he said: "I'm just relieved to hear that he's safe. I hope he will be more careful when driving in the future."
Mr Ang could not be reached for further comment.
A ComfortDelGro spokesman said Mr Weng will be receiving a certificate and $200 from the company as recognition of his act.
Said ComfortDelGro's group corporate communications officer Tammy Tan: "We are thankful that our cabby and his passengers were at the right place at the right time and had the courage to help a man in need.
"We are relieved to hear that the driver has since recovered and is doing well."
This article was first published on October 2, 2015.
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