Three people are dead and two others are in hospital after four separate road crashes across Western Australia at the start of the long weekend.

Two women died after a crash in Perth’s south, with police still looking for the passenger of one of the vehicles involved.

Police said around 7:40pm, a Toyota Landcruiser was travelling north-west on Ennis Avenue in Cooloongup, in the city’s south, when it collided with a Nissan Micra that was turning right off the same road.

The driver of the Nissan, a 27-year-old woman from Success, was taken to Rockingham Hospital but died a short time later.

The 27-year-old female passenger, from Cooloongup, died at the scene.

The driver of the Landcruiser, a 50-year-old man, failed to stop and was arrested a short distance from the crash site.

He was taken to Royal Perth Hospital and was assisting police with their enquiries.

Police are searching for the male passenger of the Landcruiser, who is not believed to be injured and has not been seen since the crash.

Motorbike rider dead

A man in his 30s also died overnight after a motorbike crash in Perth’s north.

Police said the man ran off the road into the retaining wall of a home in Quinns Rocks about midnight.

He died at the scene.

Two people in hospital

Meanwhile, two people are in hospital in Perth following separate single-vehicle crashes overnight.

The driver of a car which veered into a tree next to Great Eastern Highway, in Darlington, was taken to hospital. Photo: Supplied

In Perth, a car driving down the Great Eastern Highway, in the hills suburb of Darlington, veered off the road and into a tree, destroying the vehicle.

The male driver was taken to hospital.

Another person was taken to Royal Perth Hospital by helicopter after a crash in the south-west town of Allanson, near Collie.

‘Devastating’ start to weekend

WA Police Minister Michelle Roberts described the crashes as “absolutely devastating”.

“Only on Thursday, I was standing there ahead of the long weekend asking people to drive courteously on the roads, to take care, to be aware of the weather conditions which make it more hazardous on the roads,” she said.

“To now find that we’ve got three people deceased in the last 24 hours, and others seriously injured, is just tragic.

“My heart goes out to those families, particularly to the families of those two 27-year-old women in Cooloongup, the news for them must just be absolutely devastating and heartbreaking.”

Mrs Roberts said it was concerning that in two of the other crashes, it appeared a car hit a tree.

“Again, it’s a reminder that on country roads — and Darlington has that country road feel, too — you have to be really careful.

“The most common fatality in those circumstances is a car veering off the road into incoming traffic, or a tree.”

Mrs Roberts said it was especially important to drive safely over the long weekend, given the easing of intrastate border restrictions which allowed people to travel further.

“I understand people are excited to be back out on the roads, and some of them will be travelling quite long distances,” she said.

“Take care on the roads, show some courtesy, slow down, have breaks in your trip.”

Long weekend exodus halted

Amid the tragic start to the WA Day long weekend, many road users seeking to leave the city were delayed by construction works in the CBD.

]The southbound lane of the Mitchell Freeway was blocked off at 10:00pm on Friday, due to works on the Hay Street bridge.

The freeway lane may be shut until 2:00pm on Monday, according to Main Roads.

The bridge, which has been subject to a number of disruptive hits by trucks, is being raised from a 4.6-metre clearance to a 4.85-metre clearance.

Main Roads WA acting metro executive director Peter Sewell told ABC Radio Perth that many people travelling away from the city had left on Friday to avoid traffic.

“Yesterday afternoon, from lunchtime, around 70,000 vehicles headed to the south and around 40,000 headed to the north,” he said.

“I think the grey nomads squealed their tyres on their driveways trying to get out of the city, there were a lot of vans heading north, they’ve all been waiting with baited breath.”

Mr Sewell said it was hoped the works could be completed ahead of schedule, possibly by Sunday night, to minimise disruptions on Monday as holidaymakers returned to Perth.

-ABC