A truck that crashed into a Year 1 classroom at a Perth primary school luckily missed 22 students but the driver prematurely discharged herself from hospital.
A classroom of Year 1 students have been left traumatised but escaped injury after a runaway garbage truck crashed into their Perth primary school, trapping the driver in her cab for about an hour.
There were 22 students and a teacher in the Clifton Hills Primary School classroom in Kelmscott when the truck left the road, rolled down a slope and smashed into the building just before 9.30am on Thursday.
An Education Department spokeswoman said it was fortunate the point of impact was an unoccupied storage space in the the corner of the room.
Students and teachers in the whole school block, not just the classroom, were evacuated to another part of the school while a structural assessment was carried out, she said.
South Metropolitan assistant regional executive director Gary Anderson said the students were "highly traumatised" by the crash but they had been supported by the department's psychology service and school staff had responded well.
The 56-year-old driver was freed by emergency services and taken by ambulance to Royal Perth Hospital with multiple but non-life threatening injuries, including cuts and abrasions.
A spokeswoman said she arrived in a stable condition and was expected to spend the night, but discharged herself from the emergency department against medical advice.
WA Police Inspector Dave Dench said the cause of the crash was being investigated.
A St John Ambulance spokeswoman said it appeared the driver had accidentally knocked the handbrake.
A nearby resident, Trevor, said he saw her leaning across the seat, trying to apply the brake.
"It was on its way and I thought 'nothing's going to stop this'. Then by the time I got out the door, it was in the school," he told 6PR.