Sony declined to testify at a congressional hearing about the breach. The head of Sony Computer Entertainment suggested coordinated attacks had been used to disguise the attack. Sony has also suggested that the collective known as Anonymous was behind the attacks. The collective disavowed all knowledge of the breach, saying stealing credit card data isn’t its style. The scale of credit card loss, while large, isn’t as bad as first expected, says Sony CEO Kaz Hirai. In the United States, approximately 5.6 million account holders had credit card information on file on the system.”]
Source: https://www.darkreading.com/attacks-breaches/sony-brings-in-forensic-experts-on-data-breaches