It was just after 9am in the multicultural melting pot of Moorooka when Aguek Nyok turned up early for a haircut and ended up having to kick in the door of a burning bus.

He saw the alleged attacker, 48, run out of the bus with his clothes on fire as the casual bus driver was burned to death and the vehicle rapidly filled with smoke.

Six passengers, including a frantic mother and her two children, were trapped on board up the back as the driver side mirror blew out from the intensity of the fire.

"I realised people, they were screaming at the back door," Mr Nyok said.

"They were saying 'please open the door, please open the door'."

At first, the 31-year-old thought the driver might be able to open the door, when he realised that wasn't possible, Mr Nyok rushed to the back, side door, which he said was jammed closed by the automatic mechanism.

"It was really hard," he said.

"I came to push it with my hand, nah. And I did the first kick, nah, the second kick nah, the third kick does the time."

Mr Nyok said it took three kicks to force the door open and there was too much smoke to even attempt to rescue the driver.

Horrified witnesses, police Superintendent Jim Keogh and Commissioner Ian Stewart all praised the man's "heroic" actions.

Eyewitness Clair Savage described the taxi driver was a hero.

"I just said to him 'you just saved people's lives'," she said.

But Mr Nyok humbly played down his potentially life-saving role.

"Everybody can do that," he said.

"You help if you could. You do something if you can."