The US Federal Bureau of Investigation's Internet Crime Complaint Centre (IC3) is warning of fraudulent emails that appear to come from the FBI and US military.
"The IC3 has increasingly received intelligence of fraudulent schemes misrepresenting the FBI and/or Director Robert S. Mueller III," the centre said in an alert published Tuesday. "The fraudulent emails give the appearance of legitimacy due to the usage of pictures of the FBI Director, seal, letter head, and/or banners."
The spam is actually pumping lotteries or are phoney inheritance notifications, the IC3 said.
Other scams use the FBI's name to "intimidate and convince the recipient the e-mail is legitimate," the IC3 said. Criminals have used the agency's name in extortion e-mails and online auction scams as well.
The IC3 is a clearing house for complaints of criminal activity on the Internet. Run jointly by the FBI and the National White Collar Crime Centre, it works with other law enforcement agencies and industry to help crack down on illegal online activity.
In a separate statement, also issued Tuesday, the IC3 warned that scammers were also sending out fraudulent e-mail claiming to be from U.S. soldiers stationed overseas. "The scam emails vary in content; however, the general theme of each is to request personal information and/or funds from the individual receiving the e-mail," the IC3 said.
The emails are variations on long-running scams such as the Nigerian "419" spam, which has been "surprisingly effective at extracting large amounts of cash from victims," said Adam O'Donnell, a senior research scientist at antispam vendor Cloudmark, via email.
"Users have to be aware that anyone asking for your bank account information via e-mail, regardless of their stated reason, is trying to steal your hard-earned money," he said.