Seven men were convicted today of an £8 million boiler-room fraud, the Serious Fraud Office (SFO) said. The Spanish-based operation targeted thousands of investors in the UK applying high pressure telesales techniques to push shares in a bio-diesel company, Worldwide Bio Refineries (WBR). In fact, the company was practically worthless. One defendant, company director Redmond Johnson, 66, pleaded guilty to conspiring to defraud investors. Fellow director Dennis Potter, 72, who lived in Singapore, was convicted of the conspiracy along with John Murphy, 35, and Greg Pearson, 38, both of Marbella, Daniel Murphy, 37, and Lee Homan, 37, both of Hertfordshire, and Peter Bibby, 44, of south London, who all managed share sales. Bibby absconded before the Ipswich Crown Court trial and was convicted in his absence. There is a warrant for his arrest. Commenting on the convictions, SFO director Richard Alderman said: "This is an excellent result. Not only do boiler-room fraudsters prey on vulnerable people, they also deprive genuine businesses of the capital they need to grow. "Quite bluntly, they ruin lives. I am delighted that the SFO is playing its part in tracking down operations like these and bringing fraudsters to book." WBR was set up in 2003 and had a processing plant in County Durham that was purported to produce diesel fuel from vegetable matter. It also had a plant in Singapore producing diesel intended to be marketed in the UK. The share selling was undertaken by salesmen working from a number of boiler-rooms in Marbella and Barcelona although many of them used false names and claimed to be calling from offices Frankfurt, Stockholm or Amsterdam. The business prospects of the company and the bio-diesel market were inflated by WBR's directors and the salesmen, who claimed that substantial international business was being done and that the business's shares were valued at £110 million. Investors believed that their investment in a successful bio-diesel enterprise would net them significant short-term returns, bolstered by claims that WBR was to be floated on the stock market. These claims were bogus. The SFO found that the bio-diesel plant had no output and, with only limited imports coming from the Singapore plant, WBR was not being managed with any intention of it becoming a growing commercial success. Virtually all of WBR's revenue between 2005 and 2007 was generated by share sales. Of the £8.2 million attracted from investors, around £4 million was transferred to accounts in Cyprus, Jersey and Spain for the benefit of the boiler-room salesmen. The group will be sentenced at Ipswich Crown Court on September 23.