Most investigations into hedge fund fraud or other wrongdoing during the credit crisis have been based in the U.S., but there are signs that, despite its well-regarded framework of hedge fund managers regulation, London is seeing some activity too.

Today the Serious Fraud Office announced it had opened a criminal investigation into Dynamic Decisions’ Growth Premium Master fund after a referral by the FSA and a number of complaints about the fund management firm.

The investigation comes as the SFO’s probe into Weavering Capital continues, while a decision on whether or not to take action on Madoff’s UK operations (not a hedge fund although funds of hedge funds invested with Madoff) is expected before the end of the year.

Dynamic’s founder and CEO Alberto Micalizzi today strongly denied there had been any fraud, telling me from Milan that investors would get paid out at around the $550 million the fund was valued at in December.

The hedge fund industry may be on the way up again, but there may yet be more investigations to come before we’re back to the boom times.