LONDON (AP) _ Three businessmen Thursday were given prison sentences for cheating investors in a bogus gold-mining venture.

The executives got 60 million pounds ($100 million) selling shares in a company called Butte Mining on the stock market, with promises of a big gold-mining operation to be set up in Montana, authorities said.

But the three had exaggerated the value of the metals they could get, and the investment money was secretly shuffled through a web of offshore trust funds, authorities said. The Butte Mining shares soon plunged in value.

``The degree of dishonesty involved is so serious and far-reaching that it constitutes a flagrant disregard of the law specifically designed to protect investors,'' said the judge, Sir George Newman, as he sentenced the men at the end of an 11-month trial.

Detectives who investigated the case traveled to Hong Kong, New Zealand, Monaco, France and Switzerland to piece together what had happened with all the money.

Clive Smith, 51, from Balterley, in the British Midlands, was described by authorities as the mastermind of the scheme. He was sentenced to three years in prison and disqualified from working as a corporate director in Britain for five years.

John Clarke, 49, a founding director of Butte Mining, from Gerrards Cross near London, also got three years in prison and a five-year suspension from working as a director.

Malcolm Clews, 48, a former associate of Smith, from Conway, north Wales, was sentenced to 18 months in prison.

The jury deliberated for a record 66 hours over 14 days.