A major debt-rating firm downgraded the creditworthiness of Riggs National Corp. yesterday, citing concerns about the bank company's run-ins with regulators for violating anti-money-laundering law.

Fitch Ratings said the downgrade -- its second since April -- reflects uncertainty over Riggs's ability to earn a profit after federal banking regulators last week imposed a $25 million in civil penalties on the bank, the largest fine ever in a money-laundering case.

It also reflects greater risks created by regulators' decision to continue monitoring the bank's daily operations, including requiring managers at Riggs Bank and its parent company to obtain approval from the Office of the Comptroller of the Currency or the Federal Reserve Board before paying dividends, Fitch said.

Fitch's downgrades follow similar action by another major debt-rating firm, Standard & Poor's, which lowered its assessment of Riggs's creditworthiness in February and again two weeks ago. The nation's third big credit-rating company, Moody's Investors Service, has not yet taken action but could soon, according to sources familiar with the credit-rating process.

"To put the substantial fine into perspective, Riggs has earned just $17 million since January 2000," Fitch said in a written statement. It said the fine is likely to cause a large loss for Riggs in the second quarter and wipe out any profit for the year.

Riggs has been under investigation by bank regulators for more than a year for failing to report tens of millions of dollars in suspicious activities over several years in the accounts of foreign customers, particularly those connected to the embassies of Saudi Arabia and Equatorial Guinea. The FBI has been investigating the Saudi accounts since the terrorist attacks of Sept. 11, 2001. And at least three Senate committees have ongoing money-laundering probes that focus in part on Riggs and the bank's relationship to Saudi Arabia and other foreign governments.

Fitch said that despite the higher risks, Riggs's underlying financial situation still exceeds regulatory requirements for a bank to be considered "well-capitalized."

Riggs spokesman Mark N. Hendrix said, "Fitch's decision doesn't change the fact that Riggs is financially strong."

Separately, at a hearing of a House Financial Services subcommittee, some lawmakers criticized Riggs for its lapses and faulted federal regulators for being too slow in taking action.

Rep. Sue W. Kelly (R-N.Y.), who chaired the hearings, said "reforms in the financial regulatory structure overseeing money laundering and terror financing" may be necessary. Senate Banking Committee Chairman Richard C. Shelby (R-Ala.) and the committee's ranking Democrat, Paul S. Sarbanes of Maryland, raised similar concerns in recent hearings.

"The mechanisms we put in place to detect and report suspicious activity failed, and they failed repeatedly," Kelly said. "We no longer live in a world where such failures can be tolerated."

David D. Aufhauser, who recently stepped down as general counsel of the Treasury Department, told Kelly he favors the creation of "one uniform compliance office" to police money laundering, rather than the current system of dividing that job among various financial-service industry regulators.