The state's consumer protection division is looking into the data breach, "particularly what security measures the company took to protect consumer information," Coakley's office said in a statement yesterday. A Coakley spokeswoman, Emily LaGrassa, added that more than 30 states have asked for details on the TJX investigation or expressed interest in joining the probe.

"It's pretty fluid at the moment," LaGrassa said today. "We don't have a time frame for concluding any investigation."

TJX on Jan. 17 disclosed the security breach, in which one or more hackers penetrated the company's computer network and made off with a still-unspecified number of customer records, including credit card numbers. More than in Massachusetts, the home state of the Framingham-based company, have reported that cards they've issued have been compromised.

Coakley characterized TJX as "very cooperative" in the investigation -- phrasing that her spokeswoman repeated. "They've been cooperative, and we continue to work with them," LaGrassa said.

A TJX spokeswoman did not immediately return a phone call requesting comment on the investigation.