By Anna Pollitt, ITV News
Thousands of mobile phone users are being made to pay for receiving premium rate texts they didn’t ask for by rogue firms charging as much as £4.50 a week.
Customers across all networks have complained of seeing their bills soar after being sent unwanted messages from five-digit numbers advertising gaming services, “glamour videos” and porn.
The texts, typically sent weekly or monthly, often don't make clear how users can opt out - or even that they are being charged to receive them.
One victim, a 74-year-old retired vicar from Stornoway in the Outer Hebrides, was charged £200 for unsolicited texts for a phone he rarely used.
George MacIntosh told Mailonline he was charged for texts offering a 'TextPlayWin' service.
John Mann, the Labour MP and member of the Treasury select committee, has called for "tougher action" from the government and phone providers.
"These rogue firms are ripping people off and seem to be getting away with it," he told ITV News.
"The regulator needs to be given the powers to act decisively in this area as it clearly doesn’t have the power, both financially and operationally to crack down on these companies.
"The big question is why aren’t phone companies doing more to ensure that customers are aware of the costs of these messages?"
Over the past two years, Ofcom’s premium rate regulator, PhonepayPlus, has issued fines of more than £2 million in adjudications against 38 firms.
It has banned more than 25 organisations and individuals during that period, but the regulator told ITV News it is battling thousands of complaints.
"PhonepayPlus' Code of Practice states consumers must not be contacted or charged for premium rate services without their consent and that providers of services must be able to provide evidence which establishes consent," a spokesperson said.
It says customers targeted by the premium rate scam "should first contact the service provider" before alerting the regulator.
However, Vodafone is one provider who tells scam victims they should get in touch with the premium rate service direct - thereby leaving customers to deal the firms charging them for unsolicited messages.
Vodafone told ITV News it receives "a small percentage of the overall charge" that premium rate text firms charges customers.
Network O2 would not confirm if its makes a profit, but said that it pays an independent audit house to "continuously and proactively" monitor websites and apps offering premium text services to check that "their payment flows are compliant with PhonepayPlus and our own internal audit standards."
EE and Three refused to comment.
Consumer watchdog Which? described the scam as a "modern menace" and called on PhonepayPlus to take tougher action.
How to stop unwanted premium rate texts:
Which? advises mobile phone customers to:
1. Reply to any unwanted texts with 'STOP' or 'STOP ALL'
2. Contact your mobile network provider to complain and ask them to add a bar to your phone to stop unwanted premium rate text messages
3. Complain to the premium rate text company responsible. If it is hard to locate the company, you can use the PhonepayPlus Number Checker, which will provide the name and contact details for the company running the service
4. Complain to PhonepayPlus directly - You can call their free helpline on 0300 30 300 20 from 9.30am - 5pm Monday to Friday.
Last month it was revealed how some mobile phone customers have been victims of a new 0845 mobile phone scam charging customers up to £300 for calls they didn't make.