For a careful driver like Madam Daphne Hoon, seeing an SBS bus driver seemingly asleep at the wheel at a red light junction was too much to take.

The 33-year-old freelance nail artist took three pictures of the driver with her mobile phone.

Then she sent them to online news portal Stomp yesterday.

Her car was beside a SBS service 124 bus at 11.20am yesterday at the junction of Telok Blangah Crescent and Telok Blangah Way.

Madam Hoon, who had just dropped her two children off at school, told my paper: "I noticed the driver had his elbows on the steering wheel, so I took a closer look and saw that his eyes were closed."

The driver slept for about three minutes, Madam Hoon estimated.

He did not wake up until the light turned green and she had begun to drive off.

"He didn't even realise I had taken his picture," added Madam Hoon, who makes it a point to be alert while at the wheel.

When contacted, Tammy Tan, SBS Transit's director for corporate communications, said: "We are appalled to learn about this incident and are currently conducting a thorough investigation into the matter. We take a serious view of it."

Bus captains on average work nine hours a day, of which about 12 per cent is spent on breaks in between trips, said Ms Tan.

The story on Stomp drew mixed responses with several readers criticising the driver.

Others, however, said he could be facing some personal problems and should be given the benefit of the doubt.

But Madam Hoon added: "No matter what, you are on duty. You can take a break when you reach the terminal, but not on the journey. Being a careful driver is not enough, you have to be alert to watch out for other drivers. The passengers' lives are in his hands."