A family is grieving the death of their teenage son after a school commute turned to tragedy in Perth’s south.

The high school student was struck by two cars after getting off the bus during the morning rush in Warnbro.

Witnesses say the teenage boy stepped off a bus on Warnbro Sound Avenue just after 8am and was crossing the road.

The high school student was struck by two cars after getting off a bus in Warnbro. (9News)

They say he was clipped by one car then struck by another, dying at the scene.

“Quite sad, quite quick,” one witness told 9News.

“I had to brake and then tried to help but there was already people who knew CPR and first aid.”

Major crash investigators spent hours trying to piece together exactly what happened.

Warnbro Community High School emailed parents news of the incident and their efforts to help those affected by the tragedy.

Warnbro Community High School emailed parents news of the incident and their efforts to help those affected by the tragedy. (9News)

“Our focus is on supporting students and staff who may be impacted … while respecting the privacy of those involved,” principal Debra Bright wrote.

The stretch of Warnbro Sound Avenue is busy and locals say it’s too fast, calling for the 70km/h speed limit to be reduced.

“It makes me feel worried because I’ve got a two-year-old son, we’re right next to a busy road and I’ve always been worried about the road,” resident Rhiannon Harp told 9News.

The stretch of Warnbro Sound Avenue is busy and locals say it’s too fast. (9News)

“We’ve got two high schools just across the road from where the bus was and there is a primary school over there as well.”

The sentiment is shared by fellow resident Dilly Koloi.

“It’s even hard to get out of my own intersection, there’s quite heavy traffic here,” he said.