WASHINGTON (AP) ― Swiss bank Credit Suisse AG pleaded guilty Monday to helping wealthy Americans avoid paying taxes through secret offshore accounts and agreed to pay about $2.6 billion.

The U.S. Justice Department said it was the largest penalty imposed in any criminal tax case. It is also the largest bank to plead guilty in more than 20 years.

The settlement resolves a yearslong criminal investigation into allegations that Credit Suisse, Switzerland’s second-largest bank, recruited U.S. clients to open Swiss accounts, helped them conceal the accounts from the Internal Revenue Service and enabled misconduct by bank employees. The case is part of an Obama administration crackdown on foreign banks believed to be helping U.S. taxpayers hide assets.

Officials said a criminal charge was necessary to account for the bank’s pattern of misconduct, which included a lack of cooperation and document destruction. But the deal was structured in such a way as to allow the bank to continue operating.

The penalties will be paid to the Justice Department, the Federal Reserve and the New York State Department of Financial Services.

Attorney General Eric Holder, criticized last year after telling Congress that large banks had become hard to prosecute, appeared to foreshadow the guilty plea in a video message earlier this month in which he said no financial institution was “too big to jail.”

“A company’s profitability or market share can never and will never be used as a shield from prosecution or penalty,” Holder told a news conference. “And this action should put that misguided notion definitively to rest.”

The criminal case follows a Senate subcommittee investigation that found the bank provided accounts in Switzerland for more than 22,000 U.S. clients totaling $10 billion to $12 billion. The report said Credit Suisse sent Swiss bankers to recruit American clients at golf tournaments and other events, encouraged U.S. customers to travel to Switzerland and actively helped them hide their assets. In one instance, a Credit Suisse banker handed a customer bank statements hidden in a Sports Illustrated magazine during a breakfast meeting in the United States.

Credit Suisse chief executive Brady Dougan has said previously that senior executives at the bank were not aware that some Credit Suisse bankers were helping U.S. customers evade taxes. More than a half-dozen former bankers have been charged for their role in aiding the tax evasion. The case was filed in federal court in suburban Alexandria, Virginia, where individual bankers have been charged.

The administration’s action against Credit Suisse, a banking fixture on Wall Street, comes amid public outrage that boiled over from the financial crisis that plunged the economy into the deepest recession since the Great Depression of the 1930s. Calls for holding big Wall Street banks accountable, and sending top executives to jail, have come from consumer advocates, lawmakers and others, putting the Justice Department on the defensive.

The Justice Department’s highest-profile settlement over sales of risky mortgage securities in the run-up to the financial crisis ― the $13 billion deal among the department, state regulators and JPMorgan Chase ― was a civil case, and no bank executives were charged. Federal prosecutors in California have been conducting a related criminal investigation.

The Credit Suisse case is part of a broader crackdown on foreign banks believed to be helping U.S. taxpayers hide assets. In 2009, Switzerland’s largest bank, UBS, entered a deferred prosecution agreement with the Justice Department in which it agreed to pay $780 million in fines and turn over the names of thousands of customers suspected of evading U.S. taxes. The country’s oldest bank, Wegelin & Co., pleaded guilty in January 2013 to U.S. tax charges, admitting that it helped American clients hide more than $1.2 billion from the IRS.

The case against Credit Suisse was intended in part to combat criticism that the U.S. government has not been aggressive enough in its pursuit of banks. A report from the Senate Permanent Subcommittee on Investigations accused the Justice Department of lax enforcement and faulted the government for gleaning only 238 names of U.S. citizens with secret accounts at Credit Suisse, or just 1 percent of the estimated total.

The charges come months after the U.S. government and Switzerland reached an agreement allowing Swiss banks to settle any potential U.S. charges if they disclose extensive information about their American clients, the value of their accounts and any help they received from tax professionals.

Those settlements would include penalties for Swiss banks that helped their U.S. clients avoid taxes, and the Justice Department also could use the information to prosecute Americans for tax evasion.

The agreement signed last summer was a significant step in the long-running dispute between the two countries. In it, Switzerland agreed to ease the legal barriers of its legendary bank secrecy laws in U.S. cases so that Swiss banks would be able to turn over customer data to the U.S. authorities. In return for providing the customer information, the Swiss banks could pursue legal settlements with the U.S. authorities and avoid criminal prosecution.