A tourist has plunged more than 10 metres to her death while climbing a mountain.

Antonia Mihăilescu was on a group expedition with three other climbers in Romania’s Bucegi Mountains when the terrifying incident happened on July 11.

It is understood that around 3pm, the safety rope anchor gave way while the group was descending the Albișoara Brânei route.

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Ms Mihăilescu was positioned last and slipped first, sending all four climbers plunging more than 10 metres to the rocks below.

Ms Mihăilescu, a dentist, was with three men, aged 26-51 and a qualified instructor.

Although initially all four were conscious, she was declared dead at the scene while the others were badly injured but survived.

After one of the injured climbers contacted authorities, four helicopters were deployed to rescue the group in one of the largest mountain operations in Romania’s history.

Rescuers had to go up against difficult terrain and weather which made the operation extremely challenging.

“We instructed them over the phone: to shine a bright light, from the phone’s flash or flashlight, towards the helicopter when we are above them, so we can see them,” said Sergiu Frusinoiu, one of the rescuers, in a translated quote published by Romanian outlet Digi24.

The climbers were stranded on the rocks for three hours.

Ms Mihăilescu was the last person removed from the mountain.

The 36-year-old’s heartbroken mother said she was an experienced climber who had made it to Mount Everest Base Camp, conquered the Uhuru Peak on Kilimanjaro, and climbed mountains in Peru.

“The anchor on that rope gave way and all four fell. Toni – my Antonia – died,” she said, according to The Mirror.

“She was passionate, it was the joy of her life to go up and down. She had been to Kilimanjaro, the Rainbow Mountains in Peru… and it happened here at home.”

An investigation into the incident has been launched, with the focus on the instructor overseeing the group.

“The police are carrying out checks in terms of committing the crimes of manslaughter and negligent bodily harm,” said a spokesperson of the Romanian police.

Mr Frusinoiu said a single anchor point was insufficient.

“A python like the one I have here, only so short. And, being so short and going so little into the rock, it obviously doesn’t hold,” he said.

The Bucegi Mountains are located about two hours from Romanian capital Bucharest and are a huge tourist destination.

However, dozens die on the mountains each year.