An 11-year-old boy has died after the scooter he was riding was involved in a crash with a car in Mandurah, south of Perth.

Emergency services were called to the crash scene on Mandurah Terrace, near Stewart Street, about 5:10pm yesterday, where police say the boy’s scooter, which was not electric, had collided with a Mazda sedan.

He sustained critical injuries and was rushed to Peel Health Campus, but later died.

Ambulance outside Peel Health Campus emergency entrance.

The boy was taken to Peel Health Campus but could not be saved. (ABC News: Courtney Withers)

A 46-year-old man who was driving the car stopped at the scene, and police said he was assisting with their inquiries.

Police originally said the boy had been riding an e-scooter, but later clarified it was a push scooter.

A close-up shot of a short drive way sloping up to enter a car park from a residential street, with a 'private property' sign.

Witnesses say they saw the boy riding down a small hill onto the road on his scooter before the crash happened. (ABC News: Pip Waller)

The Major Crash unit is investigating and has asked anyone with dash cam or mobile phone footage relating to the crash to contact Crime Stoppers.

Driver distraught

Mandurah local Tyler Hutchins was leaving work and driving down Mandurah Terrace when he saw the boy riding down a small hill on the scooter.

Flowers and a teddy bear sit on a limestone wall.

Tributes for the boy have been left near the scene of the crash.   (ABC News: Pip Waller)

“He was riding from the units onto the road, and there was a hidden wall that [would have meant] he wouldn’t have been able to see any cars coming,” he said.

“He ramped straight into the Mazda and the driver didn’t have time to brake.”

Mr Hutchins said the 46-year-old driver of the sedan was an “absolute mess” following the crash.

Despite the boy receiving CPR, he could not be saved.

“As I returned home I hugged my son extra tight as you never know when you could lose someone close to you,”

Mr Hutchins said.

‘Sorry I couldn’t do more’

Nicole Jones had just finished her nursing shift and was on her way pick up her son when she came across the scene and tried to assist.

“I obviously just stopped, got out of the car, directed everyone to get him off the road,” she said.

“He obviously wasn’t breathing, didn’t have a pulse, so we started CPR. That was about 10 minutes.”

Police tape tied at one end to the base of a tree lies on a grassy slope on a street verge.

Police tape at the scene of a fatal scooter crash in Mandurah. (ABC News: Pip Waller)

She said her heart went out to the boy’s parents.

“I don’t think I’ll forget their cries for a good while now,” she said.

“Thoughts and prayers with mum and dad. And I’m so sorry I couldn’t do more.”

The boy’s death was the fourth on Western Australian roads over the Easter period, with three others killed in separate crashes since Thursday.

A 35-year-old man died after the car in which he was a passenger struck a tree on Hayman Road in Como, in Perth’s southern suburbs early Monday morning.

Flowers with a card written saying 'God has you in his keeping while we keep you in our heart'

Flowers remain at the scene for the boy, who is the fifth person to die on WA roads over Easter. (ABC News: Pip Waller)

Two people were killed on Thursday, including a 14-year-old boy struck by a car while riding his off-road motorcycle in Bedfordale, about 40 kilometres south-east of Perth.

In addition to the four road fatalities, an 18-year-old woman was killed in an off-road accident in Derby on Thursday night.

Editor’s note: This story initially said the boy was riding an e-scooter, but was amended after police issued a correction.