An American woman has been killed at a lion park in Johannesburg, it has been reported.

Reports from South African news outlet EWN say there were two people travelling in the car with their windows apparently down when the lion grabbed the woman.

Another person has been critically injured, it was said.

The Lion Park confirmed to EWN that the woman, believed to have been in her 40s, was killed this afternoon, says EWN.

The lion managed to crawl inside, killing the woman and seriously injuring the driver. The man was injured trying to push the lion off the woman.

Scott Simpson, the assistant operations manager said: "Our staff working at the top of the camp tried to get the lion away from the car. Ambulances were called immediately but it was too late," he said.

Emergency services arrived at the scene and tried to resuscitate the woman, but were unable to save her.

The lion from the enclosure has been locked up following the incident.

Simpson added: "This is not a common occurrence. We have plenty of signage at the park, indicating that windows should always be closed while driving in the lion park.

"Brochures are handed out to all of the tourists who visit the park.

"I really don’t understand why people think its okay to leave windows open."

It is not the first such attack at the attraction. In March Australian Brendan Smith posted images on Facebook of a lion attacking him at the park.

He admitted that he left his window open.

The Lion Park’s website states: "Nowhere can you get closer to a pride of Lions and other animals and still be completely safe.

"See the animals up close in all the activities that the Lion Park offers, whether you go on a self-drive tour, guided tour or in the new electric silent vehicle – we guarantee that you will get super close to the animals."

Previous guests to the popular site include singers Shakira and John Legend.

In total, lions are responsible for around 250 deaths each year.