The number of Internet users claiming to have fallen victim to premium-rate phone charge fraud has risen sharply, according to industry regulator ICSTIS.
ICSTIS has been forced to call in the National Hi-Tech Crime Unit (NHTCU) after being hit with a surge in complaints.
According to ICSTIS, some of these complaints may be due to software programs called diallers that have been secretly downloaded onto their machines.
Diallers are downloaded onto Web users' computers to allow access to pay-per-view sites, such as porn sites, but it appears they are being installed without users' knowledge and are running up large bills by connecting to premium-rate telephone lines.
The percentage of Internet-related complaints about premium-rate services has risen from 43 percent in 2002 to 70 percent in 2003, as a proportion of customers making complaints about high telephone bills, according to ICSTIS.
However, when ICSTIS investigates these complaints, it often finds that the companies concerned appear to be conforming to ICSTIS' standards, according to Suhil Baht, policy advisor at ICSTIS. This has led the regulator to turn to the NHTCU.
"If it's only a few cases, then we can put it down to the husband or kids not admitting to surfing porn, but if 300 customers are saying the same thing about one company, then we can't ignore it," said Baht. "We can't work out what the problem is, so have recently started talking to the Hi-Tech Crime Unit so they can do a criminal investigation."
A spokesperson for the NHTCU confirmed that it is in the "early stages of the investigation". One possible cause being examined is Trojan viruses installing diallers onto the computers of unsuspecting users.
"While online, the Trojan will drop your current Internet connection and reconnect you to a premium rate line. It can then change your Internet settings so that the premium-rate dialler is used as a default," said the spokesperson.
This problem is restricted to users connecting to the Internet by dial-up and can be avoided by using antivirus software, according to the NHTCU. BT has an advisory on its Web site telling customers how to avoid premium-rate dial-up scams.
Users who would like to complain about a premium-rate service provider can complain online at the ICSTIS Web site.
The problem of dial-up scams is unlikely to be resolved in the near future. The NHTCU has admitted that it is not giving the problem its full attention yet because it is concentrating its efforts on dealing with phishing crime.