Viviane Reding, a European Union telecommunications commissioner, said more than 90 percent of the sites offering mobile phone sales use hidden subscription agreements and unclear charges to mislead younger customers, The Sunday Times of London reported.
Meglena Kuneva, commissioner for consumer protection, said children were particularly vulnerable to such marketing tactics because of their impressionable age and the fashionable nature of the specialized ring tones.
"Some children as young as 5 have a phone and young people often see ring tones as a fashion statement," Kuneva said. "Children are particularly vulnerable consumers and our initial investigation into the mobile services market shows a high number of rogue traders ready to cash in on this."
The commission's findings, which were the result of a year-long investigation, will now be used to prompt necessary changes in industry regulations, the Times said.