Two men have been arrested in South Korea on suspicion of sending out 1.6 billion spam emails.

The men, aged 20 and 26, are alleged to have broken the law by sending the emails between September and December 2006.

South Korean authorities in Seoul claimed that the duo, both computer programmers, obtained personal and financial information from 12,000 victims which they then sold to other firms.

"South Korea was revealed in a recent Sophos security threat report as the third-worst nation in the world for relaying spam, so it is critical that the authorities are cracking down on spammers based in the country," said Graham Cluley, senior technology consultant at Sophos.

"Spammers are battering inboxes in their attempts to make fast money, sell fake goods and, in the worst cases, steal identities."

South Korean authorities arrested a man in May 2006 suspected of running a network of zombie computers alleged to have sent 18 million spam messages a day.