New York Attorney General Eric Schneiderman on Friday said he has launched an investigation into credit reporting company Equifax's massive data breach.

Equifax said Thursday that the breach could potentially affect 143 million consumers in the United States, and more than 8 million New Yorkers. With a U.S. population of about 324 million in 2017, the Census Bureau estimates, the breach affects a huge portion of the country.

The breach lasted from mid-May through July, when hackers accessed names, Social Security numbers, birth dates, addresses and, in some instances, driver's license numbers.

Congress will also probe the Equifax breach. Reuters reported Friday that the House Financial Services Committee will hold a hearing on the matter.

Equifax discovered the breach July 29.

Schneiderman has sent a letter to Equifax seeking additional information about the breach.

"The Equifax breach has potentially exposed sensitive personal information of nearly everyone with a credit report, and my office intends to get to the bottom of how and why this massive hack occurred," the New York attorney general said. "I encourage all New Yorkers to immediately call Equifax to see if their data was compromised and to consider additional measures to protect themselves."

Under New York law, businesses with New York customers are required to inform customers and the attorney general's office about security breaches that have placed personal information in jeopardy. The attorney general has also previously proposed new legislation to make consumer information more secure.

Schneiderman tweeted later Friday that his office had been in touch with Equifax about a controversial arbitration policy:

NY AG tweet

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