Police have charged a 20 year old woman from Canning Vale with the murder of a 17 year old male of Baldivis.
A red sports-style auto was seen at the Eucalyptus Boulevard scene with its windscreen shattered.
They used towels and sheets to put pressure on wounds and went and got water for them.
"I went to help one of the guys about 15 metres down on the road and there were two more in the bushes near the bus stop".
The Education Department has confirmed that students from Canning Vale College were involved in the melee or witnessed the fighting.
"First of all we heard a big bang and me and my husband were sitting in front of the TV, there was [a] casualty next to the vehicle - they were covered by blood", she said. "When I sat down I thought 'did that just happen?"
It's believed the violence started at a Dan Murphys store on Ranford Road around 3pm on Thursday.
Two people were stabbed, one suffering serious injuries, while police said five people were in hospital with injuries.
Four people were taken to hospital, including the male teenager who later died.
Three males, two aged 16 and a 17-year-old, remain in a serious but stable condition in Royal Perth Hospital in the state trauma unit.
So far, no charges have been laid.
At least two people were stabbed during what is believed to be a brawl on Thursday night.
"This was unrelated young people that have ended up having a disagreement and it's just ended up spilling out and becoming bigger than it really needed to be", he said.