The 47-year-old, who used the alias Yadi Zhang, defrauded more than 128,000 victims through a scheme in China from 2014-17 and stored the illegally obtained funds in Bitcoin assets.

Qian played a leading role in the scam.

After fleeing China in 2018 using false documents, she came to the UK where she attempted to launder the proceeds, according to police and prosecutors.

She faces up to 14 years in prison.

The Chinese national, who pleaded guilty to acquiring and possessing criminal property on September 29, will be sentenced after a two-day hearing on Monday and Tuesday at London's Southwark Crown Court.

A Malaysian accomplice, Seng Hok Ling, also 47, admitted to money laundering at the same court earlier and is also due to be sentenced.

Another accomplice, Jian Wen, was jailed for six years and eight months over her role in the scheme last year after being found with Bitcoin wallets worth over $2 billion.

Qian is believed to have coordinated a Ponzi scheme, which pays out to investors using funds from new entrants.

After converting a large portion of her victims' money into Bitcoin, she set about laundering the funds in the UK through property purchases including a pound23-million ($30-million) London mansion.

- Huge losses -

Police surveillance of Qian's co-defendant Ling led to her arrest in April 2024, and cash, gold and cryptocurrencies totalling pound11 million were seized.

Before the arrest, London police made what they believe to be the largest cryptocurrency seizure in history: more than 61,000 Bitcoins, worth over $6 billion at current rates.

William Glover of law firm Fieldfisher told AFP the case was "possibly the largest legal case of its kind in terms of value involving an individual and not a corporate".

Some of his clients had suffered enormous personal losses that had affected their lives, marriages and families, he said.

According to Jackson Ng of Duan & Duan, who is representing other investors, the defendant organised public events while claiming to have government support.

People who were not seasoned investors and were not "going to check everything" were drawn in and exploited, he said.

One Chinese couple, office workers in their 40s, lost hundreds of thousands of dollars they had saved for their retirement and their daughter, after attending a presentation in 2016.

The promised return on their investment stopped being paid out in 2017. Their daughter has now broken off all contact with them, Ng said.

Fuelled by growing interest, Bitcoin, which was trading at around $3,600 at the end of 2018, is currently hovering around $100,000.

Details of a compensation scheme proposed by the British authorities are still being thrashed out in London's High Court in civil proceedings.

Around 1,300 alleged victims have come forward, according to sources close to the case.

lul/zap/har/js/kjm

CROWN HOLDINGS