The hacker group Anonymous repeated Wednesday that it had nothing to do with the recent breaches of two Sony online networks that may have allowed access to credit card information.

The hacker group said in a press release that it has never stolen credit card information as part of its own cyber attacks. “If a legitimate and honest investigation into the credit card theft is conducted, Anonymous will not be found liable,” the release said.

On Wednesday, Sony dropped a not-so-subtle hint into a letter to a House Commerce subcommittee that it believes Anonymous may have been indirectly or directly responsible for the April 17- 19 attack on its PlayStation Network and online entertainment service.

Sony announced on April 26 that a breach of its PlayStation Network had compromised millions of customers’ personal information, and cautioned that credit card information may have also been stolen. On May 2, Sony Online Entertainment, another Sony division, announced that credit card data had been stolen from its servers as part of an attack.

Anonymous has admitted to executing a denial-of-service attack on Sony on April 4. However, the group said on April 7 that it would stop attacking the PlayStation Network in solidarity with Sony customers.

Sony said in its letter to the House panel that while it believes it has identified the cause of the attack, it does not know who was behind it. However, by focusing on the Anonymous denial-of-service attack, the company said it may have been delayed in discovering the intrusions into the PlayStation Network and Sony Online Entertainment.
The company also said that it found a file called “Anonymous” on one of the servers affected by the data breaches accompanied by the words “We are Legion,” a part of the group’s slogan

Anonymous has denied leaving the file.

The PlayStation Network is expected to be back online some time this week. Sony Online Entertainment has not yet said when its services will be back online.

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