Estonian police have detained a 24-year-old man suspected of stealing money from hundreds of internet bank accounts across several European countries.
The man is alleged to have sent a phishing Trojan horse, which could steal usernames and passwords by logging keyboard strokes remotely, to thousands of internet banking users.
The suspect has been detained following a year-long investigation by computer crime authorities across Europe. The man is being linked by police to the thefts of millions of pounds from accounts in the UK, Estonia, Germany, Latvia, Lithuania and Spain.
If charged and found guilty, he could face a five-year prison sentence.
It is believed the suspect spread the Trojan horse by emailing thousands of messages to internet users that promised job offers.
The offers purported to come from legitimate organisations, such as government institutions, banks and investment firms, but actually contained a link to a webpage that infected computers with the Trojan horse.
"The last 12 months have seen a dramatic rise in the number of new viruses, worms and Trojan horses designed to steal the keystrokes of innocent computer users. Our labs analyse approximately 15 new pieces of malware which include this payload every day, compared to only five a day this time last year," said Graham Cluley, senior technology consultant at security software company Sophos.
The British banking industry has published information about how online bank customers can take steps to stay safe online at www.banksafeonline.org.uk