An Indian migrant who was deliberately burnt to death behind the wheel of a Brisbane bus was the victim of a random attack that has horrified Australians, police believe.
Tributes are flowing for Manmeet Alisher, 29, a passionate singer and well-loved member of Australia's ex-pat Punjabi community, whose life ended in the most appalling way yesterday.
A passenger waiting on a Moorooka footpath climbed onto Alisher's bus just after 9am local time and hurled an incendiary device at him, engulfing the young man in flames as terrified passengers screamed and fought to escape.
Queensland Police Commissioner Ian Stewart says there was nothing to suggest terrorism or racial motivations were a factor in an attack he described as disturbing.
But he said counterterrorism authorities were involved in the murder investigation as a "precaution".
Stewart said little was known about a 48-year-old man who's been cooperating with detectives since his arrest at the scene. He was being treated for burns in hospital.
The man wasn't previously known to authorities, and police have said the attack appears random and, so far, without any obvious motive.
The attack, on a suburban commuter bus travelling through a multicultural suburb of Brisbane, could have been so much worse if not for the actions of a taxi driver who's been hailed a hero.
Stewart has publicly praised Aguek Nyok, who kicked out the back door of the bus as it stood burning and choked with smoke.
Passengers, reportedly including some children and their terrified mothers, were able to escape. Six people who were on the bus have been treated for smoke inhalation and minor injuries.
Nyok said has told of his confusion after coming across the blazing vehicle. He began kicking at a back door when he heard screaming.
"I thought the driver would open the door for them but nah, I stood a few seconds and nothing was happening so I decided to do something about it," he told the Nine Network. "Everyone was shaking ... I was just holding the door until the last one got out."
Veteran police Superintendent Jim Keogh said there was no hope for the driver, who was enveloped in flames. "He would have stood little chance."
Alisher was remembered on social media by members of the Indian community. "It's devastating news, hard to believe. He was our hero. It's very big loss to Punjabi community across the world," Baldev Singh Nijjar wrote.
Shock and anger has already started to emerge among other bus drivers, who've long bemoaned the lack of government action on driver safety.
Just four weeks ago, the Queensland Government announced a wide-ranging review into bus driver safety, after sustained pressure from drivers and the Rail Tram and Bus Union.
In announcing the review, Transport Minister Stirling Hinchliffe revealed there had been more than 350 assaults on bus drivers across the state in the previous six months.