Internet users have been warned that messages about the 'suicide' of Osama Bin Laden posted on internet message boards and usenet groups are hoaxes masking an attack on their computer.

The messages attempt to persuade readers to download a file which contains the Hackarmy Trojan.

The infection allows hackers to gain control of a computer remotely, and lurks in a file posing as photographic evidence that Osama Bin Laden has killed himself.

Thousands of messages have already been posted claiming that journalists from CNN found the terrorist leader's body earlier this week.

Typically they read: 'Osama Bin Ladin [sic] was found hanged by two CNN journalists early Wedensday [sic] evening. As evidence they took several photos, some of which I have included here.

'As yet, this information has not hit the headlines due to Bush wanting confirmation of his identity, but the journalists have released some early photos over the internet.'

Graham Cluley, senior technology consultant at antivirus firm Sophos, said in a statement: "Hackers and virus writers will try all kinds of tricks to entice people into downloading their malicious code.

"It seems this time that the hacker has focused on the public's morbid curiosity and appetite for news on the war against terror."