A group of tourists who were on a safari in Tanzania got more than they bargained for when a cheetah hopped into their vehicle for a closer look.

In a video captured by photographer Peter Heistein, the curious cheetah is seen on a back seat in the vehicle, sniffing around and checking it out.

The man in the video, Mr Britton Hayes, was told by his guide to keep still and not make eye contact with the animal, reported US news outlet Komo News on Thursday (March 29).

He was also taught to slow his breathing to keep the cheetah at ease.

Mr Hayes said his group was watching three cheetah brothers on the hunt in the Gol Kopjes of the Serengeti when the incident occurred earlier this month.

While the cheetah was exploring the inside of the vehicle, one of its brothers was also on the hood.

"But it was too late to drive quickly away or anything like that because you don't want to startle the animals, because that's when things usually go wrong," he was quoted as saying by Komo News.

He added that when it happened, he thought he was "going to die", and he could not believe he survived the situation.

"I was scared to death, but I've never felt more alive," said Mr Hayes.

The video of the encounter was posted on Facebook by his mother, Ms Elisa Jaffe, with the caption "I see people posting pics of their family vacations on the beach and at the theme park but not my family...".

"Give your mom a heart attack kid! No wonder he waited to tell me," added Ms Jaffe, who is a radio news anchor at Komo News.

This is not the first time that a cheetah has come up close and personal with safari tourists.

In 2016, another cheetah in Kenya was caught on camera leaping onto the roof of an open-top vehicle, even lying down on the roof at one point.

However, there have been other occasions where tourists were mauled to death at safari parks by the wild animals.

That same year, a tourist was mauled and killed by a tiger and another was seriously injured after they got out of their car while in a safari park in China.