The Financial Conduct Authority (FCA) has warned a scammer is operating practically on its doorstep under the name Brookes and Hargreaves.
The firm, which proportes to provide financial advice and wealth management services, is located within five minutes walk from the regulator itself, at 40 Bank Street, Canary Wharf.
The FCA warned the firm was un-authorised and was targeting people in the UK.
The firm's name Brookes and Hargreaves is not to be confused with Hargreaves Lansdown, an investment broker authorised by the regulator, which is located in Bristol.
The FCA said: "We believe this firm has been providing financial services or products in the UK without our authorisation.
"Almost all firms and individuals offering, promoting or selling financial services or products in the UK have to be authorised by us.
"However, some firms act without our authorisation and some knowingly run scams like share fraud."
Share scams are often run from ‘boiler rooms' where fraudsters cold-call investors offering them worthless, overpriced or even non-existent shares.
The FCA warned: "Boiler rooms use increasingly sophisticated tactics to approach investors offering to buy or sell shares in a way that they say will give investors a huge return. But in the end, victims are often left out of pocket - sometimes losing all of their savings or even their family home.
"We have found that victims of share fraud lose an average of £20,000 to these scams, with as much as £200m being lost in the UK each year."
Only last week the FCA and police arrested three people in connection with a fresh boiler room investigation.
The regulator and police have previously warned of ‘master lists' containing personal details of UK citizens to be targeted by fraudsters.
The biggest individual loss recorded by the police to date was £6m.
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