(Illustration/Dado Ruvic/Reuters)

An additional 2.5 million consumers may have been affected by the massive data breach at Equifax, the company said in a statement Monday, bringing the new total of potentially affected consumers to a staggering 145.5 million.

“I was advised Sunday that the analysis of the number of consumers potentially impacted by the cybersecurity incident has been completed, and I directed that the results be promptly released,” said interim chief executive Paulino do Rego Barros Jr. “Our priorities are transparency and improving support for consumers. I will continue to monitor our progress on a daily basis.”

Mandiant, the cybersecurity firm hired by Equifax to investigate the breach, has completed its analysis of affected consumers and did not find evidence of another attack or newly accessed databases, Equifax said.

The announcement comes as Equifax braces for several rounds of extensive questioning from lawmakers on Capitol Hill. Former chief executive Richard Smith is slated to testify in front of four congressional committees this week, and frustrated lawmakers are expected to grill him on the company's cybersecurity practices, its immediate response to the hack and reports of insider trading.

In prepared testimony published Monday, Smith said that he “was ultimately responsible for what happened” on his watch and that Equifax let consumers down.

Earlier this month, the credit reporting company announced that crucial, identifying information belonging to nearly half the country may have been compromised, including birth dates, home addresses and Social Security numbers. In addition to the hearings, the hack has prompted state attorneys general and several federal agencies to examine the data breach and the company's response. Security experts have warned that the long-term consequences of the hack will be difficult to fully discern. But Equifax is offering free credit-monitoring services for one year and will unveil a new service next year allowing consumers to freeze and unfreeze their credit information at no charge for life.

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