While Sony discovered that hackers had broken into their PlayStation Network on April 19, it wasn't until nearly a week later that the company understood the full scope of the breach, a Sony official tells Kotaku.
The company learned that customer data was stolen on Monday, only after an outside security firm conducted days of forensic analysis, Sony said.
US Senator Richard Blumenthal publicly questioned today Sony's failure to "immediately notify affected customers of the breach and to extend adequate financial data security protections".
The letter, written to Sony Computer Entertainment of America president Jack Tretton, echoes the concerns of Playstation Network members who have been increasingly bothered by the lack of information from Sony.
Speaking to Kotaku tonight, SCEA spokesman Patrick Seybold said the company alerted customers as soon as they were able.
"There's a difference in timing between when we identified there was an intrusion and when we learned of consumers' data being compromised," Seybold said. "We learned there was an intrusion April 19th and subsequently shut the services down.
"We then brought in outside experts to help us learn how the intrusion occurred and to conduct an investigation to determine the nature and scope of the incident. It was necessary to conduct several days of forensic analysis, and it took our experts until yesterday to understand the scope of the breach. We then shared that information with our consumers and announced it publicly this afternoon."
About 4pm EST (6am AEST) on Tuesday, Sony started notifying their PlayStation Network members that private data including names, addresses and perhaps passwords were stolen from Sony's database. The company doesn't believe credit card data was stolen, but isn't positive it is secure.