The state attorney general is asking Sony Network Entertainment to alert all Massachusetts residents who may have been affected by the massive data breach that hit the company's PlayStation Network last month, an effort Sony says is under way.

In a letter to Sony, AG Martha Coakley told the electronic giant that it must provide legal notice to affected Bay State residents, in accordance with the state's data breach notification statute.

Specifically, Sony must provide notice of the breach on its homepage, as well as notify all residents via email. It also must publicize the notice in media throughout the commonwealth.

"This is certainly a significant breach of personal information for millions of Sony customers, including hundreds of thousands of Massachusetts residents," Coakley said in a statement. "While the case remains under investigation, we believe Sony should immediately notify all of its Massachusetts consumers about the breach so that people can take steps to protect themselves."

On April 20, the PlayStation Network and Qriocity services were suspended by parent company Sony. On Tuesday of last week, network users learned from Sony that their credit card data and other personal information may have been accessed by hackers.

Sony states that sometime between April 17 and 19, some user accounts were compromised because of an illegal intrusion into the network. The network contains about 77 million user accounts worldwide.

Sony says it plans on notifying all account holders via email and recommends monitoring any credit or debit accounts associated with a PSN account for unauthorized or fraudulent activity.

- NOAH HOFFENBERG

Coakley Sony