YEAR 7 students from James Sheahan Catholic High School fled their burning bus on Friday afternoon after it caught fire on the M2 motorway in northwest Sydney.
Fire and Rescue NSW said on its Twitter page about 40 people had safely disembarked the school bus and heavy traffic was banking up at Carlingford about 3.30pm on Friday.
Inspector Phil Brooks from the NSW Police Traffic and Highway Patrol Command said the students walked back up the M2 to get out of the way of the fire.
"But this bus is well and truly on fire as we speak,” he told Macquarie Radio.
A Fire and Rescue NSW spokeswoman said the engine compartment of the bus had caught fire.
Three fire crews battled the blaze, she said.
Inspector Brooks said a senior constable who happened to be nearby on his motorcycle raced to intervene with a small fire extinguisher and would be recognised for his quick action.
He said the children had come to Sydney on a school trip.
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