An East Anglian entrepreneur is speaking out to warn others after the joy of securing £500,000 investment for his business turned to betrayal as he fell victim to an elaborate fraud.

Branding expert Simon Middleton had founded Southwold-based Blackshore Coastal Clothing, a range of menswear, alongside business partner Andy Hilton.

After a crowdfunding bid to raise the cash failed, the pair received an enquiry from an agent for an overseas investor - the start of a convoluted scam which eventually saw £15,000 stolen from the business's bank account.

The person claimed to be working on behalf of a well-known Thai businessman, whose identity Mr Middleton checked out with a business contact in Bangkok.

They decided to proceed and spoke to the investor in a video call on April 13. Mr Middleton, who has taught at University of East Anglia about branding, said: 'When I spoke to him he said his camera didn't work which should have set the alarm bells ringing, but I thought this was going to be one of several conversations.'

After agreeing to move forward with the investment, documents were passed to lawyers and Mr Middleton queried payments for clearance papers from the Thai authorities.

Fearing it may be a scam Mr Middleton contacted his bank, Barclays, to take advice. After receiving a call from a man who claimed to be a Barclays employee called Darren, the business partners decided to pull out.

Mr Middleton said: 'He asked me where this left our business and I said it left me frustrated and that we had a bit of a cash crisis.'

'Darren' said because he knew the reason for Blackshore's difficulties, he was able to lend Blackshore £25,000 to keep it running. Over the course of several calls, Mr Middleton confirmed various digits of his security code – unwittingly letting the fraudsters posing as his bank into his account.

'When I woke up I checked our account only to find the whole thing had been emptied right up to our overdraft limit,' said Mr Middleton.

Barclays repaid Mr Middleton the £15,000 – but he remains angry at falling victim to the ruse.

He said: 'It was a terrible experience to go through. I don't feel foolish, just angry because it is like somebody breaking in to your house. I am smarter for the experience but don't want to go through something like it again.'

Mr Middleton said the company was still seeking £500,000 investment for 30% of the company to cover the costs of getting the firm off the ground.

What the bank said

The scam which defrauded Simon Middleton's business of £15,000 was elaborate and played on his relief at avoiding the original fraud by winning his confidence through a false bank worker.

However, banks are unlikely to call or email you directly and will instead request you to call them.

Barclays recommends anyone who may have given details to fraudsters should contact their bank immediately.

A Barclays spokesman said: 'This was a highly sophisticated and complex scam with individuals impersonating investors and bank employees.

'Mr Middleton was alert to the possibility that all was not well with his interactions with the 'investor' at which point the discussions ended.

'In such situations where confidential information may have been revealed with a third party we would always encourage customers to alert their bank as soon as possible in order to ensure appropriate safeguards are in place.'