Kotaku has reported that the FBI is looking into a security breach that affected millions of Sony customers.

"The FBI is aware of the reports concerning the alleged intrusion into the Sony on line game server and we have been in contact with Sony concerning this matter," FBI special agent Darrell Foxworth told Kotaku. "We are presently reviewing the available information in an effort to determine the facts and circumstances concerning this alleged criminal activity."

Customers are becoming increasingly frustrated with the company’s lack of communication, particularly over whether or not credit card information has been stolen.

Sony spokesman Patrick Seybold has written in the PlayStation Blog that the company has no evidence that hackers got their hands on credit card data. But some of our readers, as well as those at Ars Technica, blame the hack for recent fraudulent charges on their cards.

Backing up customer reports that the hackers did, in fact, obtain credit card data, security researchers report seeing posts on hacker forums claiming to be selling PSN credit card data. None of the researchers, however, have themselves seen the data.

Sony did not immediately respond to a request for comment on the reports.

Kevin Stevens, a security researcher from the security firm Trend Micro, said on Twitter that he’d seen the posts, which also advertised credit card verification numbers— information Sony has said was definitely not obtained by hackers.

The hackers that hacked PSN are selling off the DB. They reportedly have 2.2 million credits cards with CVVs #psnhackThu Apr 28 15:26:31 via TweetDeckKevin Stevens

Stevens said that, without seeing the data, he didn’t know if the hackers were lying about what information they’d obtained.

In a story in The New York Times, security researcher Mathew Solnick said he’d heard reports that hackers accessed Sony’s main database, which would give them unencrypted access to all user information.

Solnick also said that he believes the attackers got into the network through a hacked console, then made their way to the company’s servers.

If you’re worried about your personal information, take a peek at our guide on to what to do if you’ve been affected by this breach.

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