Mount Everest guides have been accused of secretly drugging foreign climbers to trigger expensive aerial evacuations as part of a $20m (£15m) insurance fraud scheme, according to an investigation by the Nepali police.

Operators of mountain rescue companies in Nepal have been arrested as part of the police operation, and a police spokesperson told The Independent that a total of 32 people have been charged and 11 arrests made so far.

The scale of the scam appears to be vast, affecting 4,782 international climbers between 2022 and 2025. Police said more than 300 cases of alleged fake rescues have been uncovered, with bills totalling nearly $20m charged to climbers and insurers.

The scandal has led to new scrutiny over tour operators and guides as this year’s spring climbing season got underway on 30 March. Investigators say the scam involved multiple actors across the trekking ecosystem, including sherpas, trekking company owners, helicopter operators and hospital executives.

Six operators and managers from rescue companies were the first to be arrested on 25 January for allegedly claiming insurance money by faking the rescue of foreign tourists who they say had fallen ill while trekking, police said.

These rescue companies managed to extract nearly $20m in payouts from international insurance companies for rescues that were unnecessary or, in some cases, completely fabricated.

The Nepal Police’s Central Investigation Bureau (CIB) said the offences had caused harm to “Nepal’s national pride, prestige and dignity internationally”.

Investigators say guides used a range of methods to force helicopter evacuations, including faking medical emergencies and lacing food with large amounts of baking powder to stimulate gastric distress commonly associated with altitude sickness. Others were given medications with excessive amounts of water to trigger symptoms.

After trekkers reported nausea, dizziness or body aches, they were advised to descend and agree to costly emergency helicopter evacuations. Authorities said operators then used forged medical and flight documents to claim costs from international travel insurers.

Once a “rescue” was triggered, operators inflated costs by billing each passenger as if they had taken a separate helicopter flight, even when multiple people were flown together. Fake flight records and forged medical documents were then used to support exaggerated insurance claims, while hospitals created false admission and treatment reports – in some cases for tourists who were not actually receiving care.

This is not the first time a fake rescue network has been exposed, with a Kathmandu Post investigation in 2018 prompting a 700-page report produced by the government, along with the promise of reforms.

However, the scams appear to have continued. Manoj Kumar KC, chief of the CIB, told the Post that this was due to “lax punitive action”.

“When there is no action against crime, it flourishes. The insurance scam too flourished as a result.”

Travel insurance companies have previously threatened to remove their Nepal coverage if the scams continued.

Reports from 2019 also detail that some foreign visitors would connive with trekking firms and feign acute mountain sickness necessitating a helicopter rescue in return for cut-price expeditions. Their insurance documents were checked before they were accepted on the trip to ensure that the helicopter firm and its “agent” would be paid off.

Meanwhile, some unknowing trekkers were allegedly made temporarily unwell due to their meals being spiked with baking soda, uncooked chicken or even rat droppings.

Simon Calder, travel correspondent of The Independent, said: “Anyone who has been lucky enough to visit Nepal, meet the fabulous people and enjoy some of the world’s best trekking will be shocked to learn of this scam – which we first revealed in 2019.

“The vast majority of people and organisations involved in tourism in Nepal are honest and focused on providing the best possible experience. It’s important to seek reliable recommendations before choosing a company for your trip.”

The Independent has contacted the Nepal Tourism Board for comment.

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