A CANADIAN woman “stole” a complete stranger’s car following an almost unbelievable carpark stuff-up.

In late June, the unnamed woman rented a black Nissan Sentra from a company in Cornwall, Ontario in Canada.

Immediately afterwards, she drove to a Walmart department store for a shop before finding what she thought was her car in the car park.

The woman got into the unlocked car, pressed the keyless start button, and drove off — oblivious to the fact it was a completely different vehicle to her own rental.

Keyless cars can be operated as long as the key fob is located inside the car, which was the case in this circumstance.

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Not long afterwards, a black Nissan Infiniti, which had been parked in the same lot, was reported stolen to local police.

That car’s owner had also been shopping in Walmart before realising his vehicle had vanished.

In a lengthy Facebook post, the Cornwall Community Police Service warned motorists to never leave key fobs in cars when not in use.

They explained that for two weeks, the clueless woman “drove around and used the black car for her regular everyday activities” and only realised something was wrong after returning to the rental company to return the car.

“The woman spoke to the manager and commented about how unkept [sic] the inside of the vehicle was and the fact that there was a set of golf clubs in it as well,” the post read.

“The woman was not impressed and handed over the keys. The manager, now slightly confused, observed the keys to belong to an Infinity, a vehicle the woman did not rent.

“The manager … proceeded to ask her where she went after leaving the car rental two weeks ago. The woman informed him of her activities.”

The pair returned to the Walmart parking lot, and the woman took the manager to the spot where she had parked her rental car — only to find it still sitting there as she had left it.

“The manager and the woman, who was now confused and a wee bit embarrassed herself, returned to the car rental company and contacted police, providing the information for the Infiniti and what took place,” the post stated.

“The Infinity came back as stolen on police systems as reported in June and … both the car rental company and the Infiniti owner retrieved their vehicles and there was a happy, and funny ending to this story.”

But police urged drivers to take care.

“The moral of the story is this …. please do not leave your key fobs in your vehicle when not being operated, you never know who might take it,” the post concluded.

“Folks, we just can’t make this stuff up!”

The hilarious post has received hundreds of likes, shares and comments from bemused Facebook users, with one posting: “That happened to me once. I got into the car and I noticed different objects on the dashboard, then I noticed I got into the wrong car. I was embarrassed,” while another added: “So both of them left their car unlocked and keys in it? Talk about a comedy of errors.”

alexis.carey@news.com.au