“This cancer is metastasizing into an economic crisis for the city,” said Mayor A. C. Wharton Jr. in his riverfront office. “It’s done more to set us back than anything since the beginning of the civil rights movement.”

The mayor and former bank loan officers point a finger of blame at large national banks — in particular, Wells Fargo. During the last decade, they say, these banks singled out blacks in Memphis to sell them risky high-cost mortgages and consumer loans.

The City of Memphis and Shelby County sued Wells Fargo late last year, asserting that the bank’s foreclosure rate in predominantly black neighborhoods was nearly seven times that of the foreclosure rate in predominantly white neighborhoods. Other banks, including Citibank and Countrywide, foreclosed in more equal measure.

In a recent regulatory filing, Wells Fargo hinted that its legal troubles could multiply. “Certain government entities are conducting investigations into the mortgage lending practices of various Wells Fargo affiliated entities, including whether borrowers were steered to more costly mortgage products,” the bank stated.

Wells Fargo officials are not backing down in the face of the legal attacks. They say the bank made more prime loans and has foreclosed on fewer homes than most banks, and that the worst offenders — those banks that handed out bushels of no-money-down, negative-amortization loans — have gone out of business.

“The mistake Memphis officials made is that they picked the lender who was doing the most lending as opposed to the lender who was doing the worst lending,” said Brad Blackwell, executive vice president for Wells Fargo Home Mortgage.

Not every recessionary ill can be heaped upon banks. Some black homeowners contracted the buy-a-big-home fever that infected many Americans and took out ill-advised loans. And unemployment has pitched even homeowners who hold conventional mortgages into foreclosure.