Sony has warned that almost 25 million extra gaming users may have had their personal details taken in a hacker attack.
On Monday, it had taken the Sony Online Entertainment (SOE) service offline after a security breach.
Sony said the user data issue related specifically to SOE and emerged as it was investigating the problem.
Last week, Sony admitted that the personal details of 77m Playstation users may have been stolen by hackers.
In a message to its customers, Sony said: "We had previously believed that SOE customer data had not been obtained in the cyber-attacks on the company."
However, it added that "on 1 May we concluded that SOE account information may have been stolen".
Sony was quoted by the Associated Press (AP) news agency as saying that the latest incident occurred on 16 and 17 April.
This was earlier than the larger Playstation user security breach.
Sony said that during the most recently discovered security breach, names, home addresses, e-mail addresses, dates of birth, phone numbers and gender information was taken.
Additionally, direct debit details of around 10,700 customers in Austria, Spain, the Netherlands and Germany were stolen, as were the credit or debit card details of some 12,700 non-US customers.
Sony explained that the information included card numbers and expiry dates, but said that it was taken from a 2007 database which was securely encrypted.
Spokeswoman Taina Rodriguez was quoted by AP as saying that there was no evidence as yet that the stolen information had been used for illicit financial gain.
The suspension of SOE, which is based in San Diego, California, was announced in a brief statement on its website, Station.com.
Multiplayer games including DC Universe and Facebook-based Fortune League were unavailable as a result.
"We have had to take the SOE service down temporarily," the company said.
"In the course of our investigation into the intrusion into our systems we have discovered an issue that warrants enough concern for us to take the service down, effective immediately," it added.
The company had previously said that it would get the Playstation network up-and-running again this week.
It said users would see a phased re-introduction of gaming, movie and music download services.
Playstation Network has been unavailable since 20 April.
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