In one of the biggest internet security breaches, a hacker broke into Sony's PlayStation video game online network and may have obtained access to personal data of about 77 million users, including credit card information, addresses, user names and passwords.

In a blog post, Sony's Senior Director, Corporate Communications & Social Media, Patrick Seybold said, "an unauthorised person" has obtained the name, address (city, state, zip), country, email address, birthdate and password and login of users' PlayStation Network as well as of Qriocity digital music service.

Other information like profile data, including purchase history and billing address and PlayStation Network password security answers may also have been obtained by the hacker.

Sony said it is possible that the hacker has obtained access to credit card data, including credit card number and expiration date.

Sony had 77 million accounts as of March 31 for its PlayStation Network.

"We have discovered that between April 17 and April 19, 2011, certain PlayStation Network and Qriocity service user account information was compromised in connection with an illegal and unauthorized intrusion into our network," Seybold said.

While there is no evidence that "credit card data was taken, we cannot rule out the possibility. If you have provided your credit card data through PlayStation Network or Qriocity, out of an abundance of caution we are advising you that your credit card number (excluding security code) and expiration date may have been obtained," the company added.

Sony said it expects to restore some services within a week.

In response to this intrusion, Sony has temporarily turned off PlayStation Network and Qriocity services and is investigating what happened.

Sony said it has advised users to be aware of email, telephone, and postal mail scams that ask for personal or sensitive information saying the company itself will not contact users asking for their credit card numbers or other personally identifiable information.

The company said that users should change their passwords once the PlayStation Network and Qriocity services are fully restored.

The PlayStation Network is used by owners of the company's game machine to play against one another, chat online and watch movies streamed over the Internet.

The network links users via the Sony PlayStation 3 console to game downloads and online services such as Netflix video streaming service.