The PlayStation Network is used for online gaming and sales of Sony gaming software. Qriocity runs on the same network infrastructure and provides audio and video services for some of Sony's consumer products.

The problems began around midday last Thursday Japan time -- or Wednesday evening in the U.S. -- when users were greeted with an error messages when they tried to log into the services.

Sony initially expected to have the service up and running within a day or two. Last Friday it disclosed the problems were the result of "," and on Saturday said it was "rebuilding its network" and adding additional security.

The fact that personal data was compromised as early as April 17 suggests the hack took place a few days before users started noticing problems with the service.

Sony now advises users to "remain vigilant" and be on the lookout for e-mail, telephone and postal scams. Hackers will sometimes use personal data they have stolen to target users with phishing attacks or try to trick them into handing over further data.