Britons fear being ripped-off online more than gun crime, climate change or even contracting MRSA in hospital, a survey has suggested.
Online fraud worries four out of 10 Britons, according to a survey from 3V, an electronic payments company.
The survey also found 48% of online shoppers had concerns about using their credit or debit cards online.
In addition, one in seven people said they knew someone who had suffered at the hands of Internet fraudsters.
Last month, the Financial Services Authority (FSA), the City watchdog, said it had seen an 8,000% increase in fake Internet banking scams in the past two years.
But the FSA added that the amount of money stolen by the fraudsters was still relatively small.
Nevertheless, fraud expert Professor Martin Gill warned that fraudsters are increasingly turning from offline fraud - such as using fake credit and debit cards in shops - to online scams.
"With the introduction of chip-and-pin on the high street, fraudsters have turned to other means to make their money," he said.
"The Internet is a dangerous place to be giving out personal information without taking basic precautions."
Precautions Internet users can take include not using the same password for all bank accounts and not replying to emails which request personal information.
YouGov surveyed nearly 2,500 people on behalf of 3V.
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