A TAXI driver and an English tourist who had just arrived in WA are dead after a stolen 4WD under police surveillance slammed into their vehicle.

The powerful four-wheel-drive collided with the taxi just before 2am at the intersection of Orrong Road and Leach Highway on the border of Kewdale and Welshpool.

Police revealed the taxi passenger, a 36-year-old British tourist, had just arrived on a flight into Perth and was making his way into the city. He would have been in WA for little more than an hour.

The 4WD was allegedly being driven at high speed and was being "monitored'' by a police helicopter directly overhead. Debris was strewn over a large stretch of the road.

The 28-year-old male taxi driver, believed to an Indian national, and the British man died at the scene.

PerthNow has learned that the UK tourist, believed to be a physics doctor, had planned a two-week trip in Perth for a conference.

It is believed the Indian taxi driver had been living in WA with his wife and family for some time.

An earlier police chase of the stolen 4WD was abandoned when the 4WD was allegedly being driven without lights and the pursuit was deemed too dangerous to continue.

DRIVER CHARGED WITH MANSLAUGHTER

Major Crash investigators this morning interviewed the 23-year-old driver of the Toyota FJ Cruiser at Royal Perth Hospital where he is recovering after surgery to a suspected broken leg and charged him with two counts of manslaughter.

A magistrate will preside over a bedside hearing today.

Assistant Police Commissioner Gary Budge said the taxi driver had collected the English tourist from Perth Airport and had been driving along Leach Highway towards the city when the stolen Toyota allegedly ran a red light and crashed into the taxi at speed on the Orrong Road on-ramp.

Mr Budge said the road pursuit had been aborted about 6km before the crash at the intersection of Canning Highway and Berwick Street in Victoria Park when the helicopter reported that the 4WD had its headlights turned off.

But he confirmed the police helicopter was tracking the stolen car at the time of the deadly crash. It is believed police filmed the collision from the air.

"The police helicopter maintained observations of the vehicle which subsequently crashed some time later at the Kewdale intersection,'' he said.

"I want to emphasise that there is no evidence at this time to suggest the vehicle was being pursued at the time of the crash.''

The crash was witnessed by officers aboard the police helicopter and police were immediately called to the scene, he said.

"The helicopter, as it does, provides observations from the sky, usually from a covert perspective above the vehicle. It's unlikely that people in these vehicles obtain a sight of the helicopter.

"We were certainly in a position where we were able to deploy police officers to locations, where if necessary, we would be able to deploy stingers if a chase happened with the vehicle again.''

Police said the 4WD Cruiser had allegedly been stolen from Secret Harbour on Tuesday and was being tracked by police over a series of offences across Perth this week. He declined to detail the offences, but confirmed that police were still seeking a number of other people over the crimes.

Mr Budge extended his heartfelt condolences to the families of the dead men.

"It is difficult to imagine the trauma that two families must be feeling out there today and I want to pass on my condolences to both of those families and tell them we will provide all the support that is possible to both of them,'' he said.

The Major Crash Squad and Internal Affairs Unit will investigate the circumstances of the crash and prepare a report for the State Coroner.

Police are asking anyone with information on the crash to call Crime Stoppers on 1800 333 000.

Parts of Orrong Road remained closed for some hours early today.

UNION DEMANDS TOUGHER PENALTIES

WA Police Union president George Tilbury extended his sympathy to the families after this morning's tragedy and demanded new pursuit laws to protect police and innocent community members as a matter of urgency.

He described the current $300 penalty for people who evade police as "absolutely pathetic'' and called for it to be bolstered.

"We have been working with the government for some time and we do need legislation that does act as a deterrent and makes offenders stop,'' Mr Tilbury said.

"We want to see legislation introduced that has a term of mandatory imprisonment for any offenders that fail to stop for police and put innocent lives at risk.

"Two innocent lives have been lost. We certainly don't want to see any more lost and action needs to be taken now.''

In June, police union delegates voted to ban pursuits unless the government legislated to protect officers involved in high-speed chases.

They ruled that significant inroads into the laws needed to be in place by October 1 or they would recommend that their members refuse to engage in pursuits while on duty. Last month, the pursuit ban threat was delayed until December 5.

Under draft amendments to the Road Traffic Act, the government has proposed mandatory sentencing for a new offence of evading police and provides legislative protection for officers involved in chases.

The threatened pursuit ban comes after a Gang Crime officer was charged over the death of innocent Dianella mother Sharon D'Ercole, 50, in April.

Mrs D'Ercole was killed and her daughter Lashay, 16, injured when a stolen Audi sedan being pursued by police ran a red light and slammed into their Toyota Corolla in Dianella.

* Editor's note: Comments on this story cannot be published now that charges have been laid.