Organisers of the 2006 World Cup in Germany are warning fans that a computer virus disguised as a ticket confirmation should be ignored as it is a virus.

Fans receiving emails from the email addresses ticket@fifa.de and Gewinn@fifa.de should not open the attachments supposedly confirming ticketing arrangements for next year's tournament.

The attachment is the computer worm, known as Sober-N, was identified on Monday, and has been spreading dramatically.

Clicking on the attachment will trigger the worm to harvest all the e-mail addresses on that computer, and send the same message to everyone on it. It will not however delete any of your files.

The virus warning comes as Fifa released the next wave of tickets for the tournament earlier this week.

Tickets will be allocated on a 'first come, first served' basis, i.e. applications will be processed in the order they are received. The second period features exclusively TST (Team Specific Ticket) series.

A total of 147,000 TST series initially went on sale in the first period from 1 February to 31 March 2005. This form of ticket is already sold out for the following nations: Germany, Argentina, Brazil, England, Ireland, Italy, Japan, Mexico, Netherlands, Portugal, Spain, Sweden and the USA.