Four friends died in a burning Tesla after a crash broke the car's electronic door handles, it is claimed.

A woman in her 20s was the only survivor of the fiery October 24 crash after Rick Harper, a heroic Canada Post employee, smashed the window of the blazing Model Y with a metal pole.

Four of her friends, identified as 25-year-old Neelraj Gohil, his sister Ketaba Gohil, 29, Jay Sisodiya and Digvijay Patel all died in the tragedy.

Harper has since told the Toronto Star that the surviving woman 'couldn't open the doors' from the inside of the wreck.

Teslas have a button which the car's driver and passenger push to open a door, instead of a handle. But if the power fails after a crash, the doors can become stuck and won't open.

?I would assume the young lady would have tried to open the door from the inside, because she was pretty desperate to get out,? Harper said.

?I don't know if that was the battery or what. But she couldn?t get out.?

Harper said the woman scrambled out of the car head-first after he smashed the window.

The smoke was so thick he didn't realize there were others trapped inside. He has no way of knowing whether they, too, were frantically trying to get out of the Tesla.

Police said the car crashed into a guardrail at high speed along Lake Shore Boulevard East in Toronto.

Investigators are still to determine the exact cause of the crash.

Tesla boasts of a 'safety-first design' which makes them 'the safest in the world'.

There is a manual override button in Tesla cars but experts say the feature is not widely publicized.

It directs crash victims to pull away a panel in the door and then tug at a cable underneath, which will open the doors.

Safety watchdogs have also highlighted that crash victims may be too panicked or dazed to search for the feature after an accident.

According to the National Highway Traffic Safety Administration, there are nine investigations involving the Tesla Model Y ? which is the same car involved in the tragedy.

These investigations range from 'unexpected brake activation' to 'sudden unintended acceleration'. (Daily Mail, but headline rejigged)

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