Security cameras have captured the moment flames engulfed a bus, forcing passengers to flee, on a busy road in inner Sydney.Key points:Operator Transit Systems said the bus was serviced last monthInitial investigations found the fire did not originate in the engine bayNSW Premier Gladys Berejiklian said she was confident Sydney busses were safeKenny Brown, 71, was behind the wheel of the bus when it lost power on Parramatta Road in Glebe yesterday evening.Soon after he stopped, smoke began billowing from the front of the vehicle, and within minutes, it was a raging inferno. The veteran bus driver of 12 years quickly ordered his four passengers to evacuate. Witnesses watched on as the vehicle burst into flames.”Two bystanders came and helped me with the fire extinguisher to no avail,” Mr Brown said.”It was just fruitless, the flames just engulfed the bus.”They stood there initially as though it was going to be OK. And I said, ‘no move right away, we’re going nowhere’,” he said.A series of explosive noises and the smell of burning plastic alerted business owners and residents to the unfolding emergency.”It was like boom, boom, boom. It was a bit scary because it’s really close to our shop,” witness Tammy Wong said. Bus driver Kenny Brown was praised for his quick thinking around evacuating passengers.(Supplied)”I’d say we’re about 40 metres from the site of the fire and you could feel the heat pulsating and radiating towards you.”Nearby buildings were evacuated as firefighters attacked the flames, which reached about 5 metres high. “We’re next to an old building, with a lot of timber involved, so we worked very hard to keep the fire away,” Station Commander John Downing said.The bus operator Transit Systems said the bus was last serviced in December 2020, in line with its maintenance schedule. “Initial reports suggest that the fire started at the front of the bus, indicating that it was not an engine bay fire,” a spokesperson said in a statement.”We will continue to work with the Office of Transport Safety Investigations (OTSI) to determine the cause of the fire.”NSW Premier Gladys Berejiklian said she was confident Sydney’s buses were safe.”It’s a scary situation but I have confidence that our transport authorities will get on top of that, get to the root cause and make sure it doesn’t happen again,” Ms Berejkilian said.