'Psst...want the tools to be a cybercriminal?'

Some websites are now offering surfers the chance to download free "phishing kits" containing all the graphics, web code and text required to construct the kind of bogus sites used in internet phishing scams.

According to security firm Sophos, the kits allow users to design sites that have the same look and feel as legitimate online banking sites that can then be used to defraud unsuspecting users by getting them to reveal the details of their financial accounts.

Graham Cluley, senior technology consultant at Sophos, said: "By putting the necessary tools in the hands of amateurs, it's likely that the number of attacks will continue to rise."

Sophos warned that many of the kits also contain spamming software that enables potential fraudsters to send out thousands of phishing emails with direct links to their DIY fraud sites.

"The emergence of these 'build your own phish' kits means that anyone can now mimic bona fide banking websites and convince customers to disclose sensitive information such as passwords," Cluley said.

Many online banking websites now carry messages urging users not to open any email that they suspect may be fraudulent and to telephone their bank for further information if they do receive suspicious email.

James Sherwood writes for ZDNet UK