Just after 9:00am on Friday, a bus carrying six passengers pulled into the Moorvale Shopping Centre in Brisbane's south.
"At that time that one of the passengers entered onto the bus and poured a flammable liquid onto the driver and subsequently the driver was set alight and is now deceased," Superintendent Jim Keogh said.
The bus driver has been identified as 29-year-old Manmeet Alisher.
He died at the scene and11 passengers have been treated by paramedics for smoke inhalation and minor injuries.
"The fire was substantial, he would have stood little chance."
A 48-year-old man located at the scene is in police custody.
"It is a senseless, needless taking of a young life of a person who was supporting the community by providing public transport," Keogh said.
"No apparent motive" had been identified by police, he said.
An industry colleague told AAP Alisher was a softly spoken and courteous man who recently performed at Diwali, the annual Hindu festival of lights, in Adelaide and also recited poetry.
"One of those genuine guys. It's very sad, everyone's in shock,” the man, who asked not to be named, said.
Gina Rushton is a breaking news reporter for BuzzFeed News and is based in Sydney.
Contact Gina Rushton at firstname.lastname@example.org.
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