The SFO has seen the number of large-scale investment frauds under investigation rise by more than 40 per cent, from 14 to 20 over the last year.
George Staple, the SFO director, warned investors to be on their guard, to check who they are dealing with and to take independent advice before parting with their money.
Including other smaller cases that now go to the SFO instead of the Crown Prosecution Service as a result of a change of Government policy, the total of investment frauds in the SFO workload is now 29. Tougher City regulation is also driving the alleged fraudsters into unregulated areas, such as ostrich farming, where the absence of a financial watchdog makes it easier for them to operate.
Mr Staple said: "As the economy strengthens, there is more money available for investment schemes, some of which are going to be fraudulent."
The SFO's annual report also reveals that Mr Staple has not dropped inquiries into the Barings affair, despite his refusal to press for the extradition of Nick Leeson while he was in Germany.
The report says: "We are carefully considering whether grounds exist for further criminal inquiries into other aspects of the case in England."
The SFO is believed to be keeping a close eye on the inquiry into Barings by the Commons Treasury Select Committee, where one witness, Ron Baker, used parliamentary privilege to make public accusations of a cover-up by named former colleagues. It is also on the alert for any new evidence from Singapore. The watching brief is not thought to be aimed at prosecuting Mr Leeson when he returns from his six-year prison sentence.
Mr Staple's report also makes it clear that he has not dropped another high-profile case, that against Asil Nadir, the former Polly Peck head who is now in northern Cyprus. "A warrant has been issued for his arrest and we are ready to proceed with the prosecution against him when he returns or is returned to the jurisdiction," says the SFO.
The total case book rose from 52 in April 1995 to 70 at the end of March, and the money involved has risen pounds 1bn to pounds 3bn over the last year. Further cases, including Sumitomo, have since raised the number to 77.
In 10 out of 11 SFO trials during the year the principal defendants were convicted - the odd one out being the high-profile Maxwell trial.
The rise in case load is partly due to the threshold for an SFO inquiry being lowered to pounds 1m from pounds 5m. But Mr Staple's budget has fallen pounds 600,000 this year to pounds 10.1m and he said he was pressing for a switch of funds from the CPS to the SFO.
The report discloses that the SFO issued 83 section two notices last year on behalf of 15 foreign investigatory bodies under new powers to help fight international fraud.Reuse content