'FBI, CIA' e-mails spread virus

Washington - A scam involving e-mails appearing to come from the FBI or CIA has unleashed a computer virus that spread rapidly worldwide, United States officials and security experts said on Tuesday.

The Federal Bureau of Investigation (FBI) released a statement on its website noting that the agency was not the source of the e-mails. But experts said the virus was propagating because the authors made the message appear authentic.

The FBI statement said recipients of this or similar messages "should know that the FBI does not engage in the practice of sending unsolicited e-mails to the public in this manner".

The messages appear to be sent from an e-mail address such as mail@fbi.gov, post@fbi.gov, admin@fbi.gov or a similar address, and direct the recipient to open an attachment to answer question. The opening of the file activates the virus and causes it to spread to others.

The internet security firm Sophos said similar e-mails may appear to come from the Central Intelligence Agency (CIA), but that both contain a strain of the Sober virus that has been spreading worldwide.

The worm -- named "Sober X" -- has spread so far so fast that the CIA and the FBI put prominent warnings on their Web sites making clear that they did not send out the e-mail and urging people to not open the attachment.

Across the Atlantic Ocean, Austria's equivalent to the FBI is investigating a flurry of similar bogus e-mails sent in its name to people in Austria, Germany and Switzerland, the Associated Press reported.

"This particular virus is a mass-mailer worm and is the largest one we have seen this year," said Alfred A. Huger, senior director of engineering at Symantec Corp., which sells Norton AntiVirus software. "It's as bad as it gets. With this particular type of virus on your system, there is a high probability that your personal information will be stolen."