Scammers are using Pentagon email accounts that were exposed when hackers cracked a defense contractor's computer system to make fake online orders.
A July leak of 90,000 military email addresses and passwords has helped swindlers commit online fraud, FBI officials said.
The hacktivist group Anonymous on July 11 announced it had obtained, and later posted, the confidential data by cracking a computer system at defense contractor Booz Allen Hamilton.
Now, imposters are using the traditionally trustworthy dot-mil addresses to place sham orders with e-commerce vendors, warned the Internet Crime Complaint Center, an FBI-led public private partnership. Businesses have witnessed an increase in fake dot-mil orders during the past 30 days, according to the center.
"As a result of this posting, merchants have reported some orders containing military email addresses have been identified as fraudulent," stated a center advisory issued Thursday. "Until this time, military email addresses typically meant an order was less likely to be fraudulent."
Simultaneously, the U.K. Metropolitan Police Service's Central e-Crime Unit on Friday announced that on Sept. 1 authorities arrested two men in their 20s believed to be from Anonymous and a similar prankster group called LulzSec for computer offenses committed under the online alias "Kayla."
"The arrests relate to our enquiries into a series of serious computer intrusions and online denial-of-service attacks recently suffered by a number of multinational companies, public institutions and government and law enforcement agencies in Great Britain and the United States," e-crime unit Detective Inspector Mark Raymond said in a statement.
Anonymous, which is known for defacing and taking information from websites it dislikes, seems to have targeted Booz Allen for its role in several government surveillance programs.
A note Anonymous published on a file-sharing website in July ridiculed Booz Allen's data safeguards. Given the firm specializes in defense and national security consulting, "you'd expect them to sail the seven proxseas with a state-of-the-art battleship, right?" it stated. "We infiltrated a server on their network that basically had no security measures in place."