Two passengers on board an SMRT service 961 bus were injured when it stopped abruptly while travelling along Jalan Bukit Merah towards Geylang.
Both passengers were taken to hospital after the incident, which happened at 11.20am on Friday.
The bus driver reported that he had applied the brake when approaching a traffic junction, said Mr Patrick Nathan, SMRT's vice-president of corporate information and communications.
Mr Deng Jian Xiang, a 68-year-old passenger, told evening daily Lianhe Wanbao: "The driver looked like he was trying to speed past the amber light but could not make it in time, so he ended up braking sharply."
Madam Deng Xiu Qin, 72, suffered injuries to her ankles and head. She was taken to hospital, along with another elderly woman.
"Her ankles became swollen and they hurt so badly she could not stand up. I asked the bus driver to call for an ambulance," said Mr Deng.
He added that after the incident, the bus driver got up and helped several passengers back to their seats before continuing to drive for about five minutes.
At that point, the passengers started complaining about their injuries, so he pulled over at Kim Tian Road and waited for the ambulance to arrive.
The other elderly passenger who was taken to hospital is scheduled for surgery.
She reportedly suffered a fracture to her right ankle as well as bruises to her knees and head, said her daughter.
She added that her mother tried to hold on to the handrail when she heard a bang but fell out of her seat.
Mr Nathan said the incident is being investigated.
"Our customer relations team is in contact with the two injured passengers to assist them as best we can.
"We are sorry for the distress and inconvenience this incident may have caused to our passengers."
On the same day, the driver of SBS bus 87 was seen doing a little dance while driving.
He was seen clapping, tapping his feet on the floor and moving his head from side to side, a passenger, Mr Tan, told Shin Min Daily News.
He became worried for his own safety as he watched the driver, and used his mobile phone to record the little routine.
Ms Tammy Tan, senior vice-president of corporate communications at SBS Transit, said: "We have made it clear to all our bus captains that we do not tolerate unsafe driving practices. This certainly qualifies as such.
"We will be taking stern disciplinary action against the bus captain in question."
This article was first published on April 26, 2015.
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