LOS ANGELES — The NAACP sued a dozen mortgage lenders yesterday, claiming the companies discriminated against blacks by steering them into higher-interest, subprime loans while giving more favorable loan terms to white borrowers.

The lawsuit, which seeks class-action status, was filed in U.S. District Court in Los Angeles.

It demands a court order barring the lenders from discriminating against blacks and compelling them to comply with fair housing and credit laws.

Among the defendants named in the suit are Ameriquest Mortgage Co., Citigroup Inc., HSBC Finance Corp. and Washington Mutual Inc.

Ameriquest, Citigroup and HSBC defended their lending practices as fair.

Seattle-based Washington Mutual Inc. declined to comment, saying it needed to review the lawsuit.

Subprime loans are often aimed at borrowers considered by lenders to be a higher risk because of spotty credit histories. Borrowers who obtain such loans can end up paying much more interest.

Many people who took out adjustable mortgages or home equity loans at subprime interest rates in recent years have been unable to keep up with increasing payments.

That has contributed to a spike in defaults and foreclosures in recent months, with dozens of mortgage lenders going out of business or filing for bankruptcy protection.

In the lawsuit, the NAACP contends the lenders have engaged in "institutionalized, systematic racism" and that black homeowners who received subprime loans from the lenders in 2004 were 30 percent more likely to get higher interest rates than white borrowers with the same financial qualifications.

The civil rights group cited studies and public statements attributed to government agencies and other groups that assert blacks have been more likely to receive higher-interest loans than other borrowers.

Chris Orlando, a spokesman for Ameriquest, a unit of Orange-based ACC Capital Holdings, one of the nation's largest subprime lenders, said he could not comment on specifics of the lawsuit because the company had not yet seen it.

He added, however, that company lending decisions are based "strictly on objective, statistically proven risk factors."

Christina Pretto, a spokeswoman for New York-based Citigroup, said the company is "absolutely committed to fair lending practices and adheres to what we certainly believe are the leading lending practices in this industry."

Diane Bergan, a spokeswoman for Prospect Heights, Ill.-based HSBC, said the company is confident that it is treating its customers "fairly and with integrity."