"Huge" investment frauds in Britain: investigators

LONDON (Reuters) - The credit crunch has sparked a raft of huge investment frauds in Britain but conviction rates are improving, investigators said on Thursday.

Fears over widespread investment swindles have escalated this year following the unraveling of an alleged multibillion-dollar fraud run by Wall Street financier Bernard Madoff.

"The growing number of frauds in the City and the deepening recession has prompted speculation that Britain could soon see its first one billion pound ($1.4 billion) fraud," City of London fraud investigator Detective Superintendent Bob Wishard told the Independent newspaper.

"I'm not aware of anything as big as one billion pounds, but there are undoubtedly some huge investment frauds going on -- mini-Madoffs -- that, in the fullness of time, will come to our attention."

Britain's Serious Fraud Office has come under increasing pressure to deliver more successful prosecutions.

SFO Director Richard Alderman said conviction rates had got better -- 80 percent since April 2008.

"This is the year that I am expecting delivery," he told the Independent. "I am expecting to send out some very strong messages as a result of what we are getting out into court."

"We are talking about quite large-scale fraud as a result of the credit crunch."

(Reporting by Matt Falloon; Editing by Gary Hill)