The bank must “go beyond what has been asked of us by our regulators by reviewing all of our operations — leaving no stone unturned — so we can be confident we have done all that we can do to build a better, stronger Wells Fargo,” Chief Executive Officer Tim Sloan said in a statement Friday.

The Consumer Financial Protection Bureau is looking at whether consumers were “unduly harmed” by the bank freezing and closing accounts that had suspected fraudulent activity, as well as investigating the lender’s polices around paying for mortgage rate-lock extensions, the San Francisco-based company said Friday in a regulatory filing. Wells Fargo also said in the filing that issues in its auto lending business may spark investigations, even beyond the practice of forcing unwanted insurance onto customers that the company disclosed last month.

Wells Fargo didn’t say in the filing whether any regulators were investigating the bank for charging customers for what’s known as collateral protection insurance. In an interview last month, an executive said the bank had notified at least three regulators — the Office of the Comptroller of the Currency, the CFPB and the Federal Reserve — about the insurance issue roughly a year ago.

The expansion of the lender’s fake-accounts review to include three more years and a new methodology in finding affected customers will probably lead to a “significant increase” in cases, Wells Fargo said. The bank aims to have its consultant complete the review for an expanded period by the end of this quarter and doesn’t expect the incremental costs from reimbursing more customers to have a major financial impact.

As many as 3.5 million unauthorized deposit and credit-card accounts were opened going back to 2002, lawyers representing consumers in a class-action lawsuit have claimed. Wells Fargo’s consultant pinpointed as many as 2.1 million bogus accounts in a review covering about four years through May 2015.

The lender said it’s refunded $3.26 million to customers affected by the bogus accounts scandal, a $60,000 increase from what it reported in the first quarter.

Wells Fargo shares dropped as much as 2.8 percent in New York trading, reversing gains earlier in the day, before falling 1.1 percent to close at $52.84. That was the worst performance in the 24-company KBW Bank Index.

Legal Costs

Separately, the company said it self-disclosed instances where foreign banks used “a Wells Fargo software-based solution” to finance trade involving nations prohibited by the Office of Foreign Assets Control. Wells Fargo is cooperating with a U.S. Department of Justice inquiry on the matter, it said. That probe was first mentioned in March.

Wells Fargo’s “reasonably possible” legal charges could surpass its reserves by $3.3 billion as of June 30, up from an estimate of $2 billion at the end of March, according to the filing.

Part of the increase was from “existing mortgage-related regulatory investigations,” the lender said Friday. Wells Fargo is among a handful of major banks that have yet to resolve Justice Department probes into residential mortgage-backed securities issues, according to Bloomberg Intelligence. Barclays Plc was sued by the government in December after it failed to reach a deal, while Credit Suisse Group AG and Deutsche Bank AG both settled within the last year.

In addition, Wells Fargo’s board is reviewing its own “structure, composition and practices,” which will lead to actions to be announced later this quarter, Sloan said, without elaborating.