The shady world of rogue diallers and premium rate phone scams comes under the spotlight today following an investigation by the BBC's Money Programme.

The half-hour film reveals how criminals exploit premium rate services and run rings round regulator ICSTIS. Programme makers managed to track down and interview someone who has been involved in such scams. He tells how scammers are able to dial millions of phone lines over a weekend telling punters they'd all won a prize. Even with a tiny percentage of people responding and calling a £1.50 a minute number to claim their prize, scammers are able to net hundreds of thousands of pounds.

What's more, some scammers are so business-like in their approach to ripping off punters they factor in the cost of a £100,000 fine from ICSTIS as part of their overheads.

But the programme is also critical of ICSTIS with many of those targeted by scammers believing that they do not receive the protection they would expect from the regulator.

In an interview as part of the programme the head of ICSTIS George Kidd denies that the regulator is "toothless" even though one PRS fraud victim - who's prepared to go to court rather than pay up - called for ICSTIS to be "taken out back and horse whipped because they're full of crap".

The Great Phone Call Con, a Money Programme investigation into telecom fraud, is due to be broadcast tonight (Friday November 11) at 7 pm on BBC2. ®