The mobile home subsidiary of Warren Buffett's Berkshire Hathaway is strongly denying renewed accusations that it exploits minorities, as the controversy threatens to seep into the 2016 presidential race.

In the third installment of an investigative series that began in April, The Seattle Times and BuzzFeed allege that Clayton Homes, the country's biggest maker of new "manufactured" homes, "systematically pursues unwitting minority homebuyers and baits them into costly subprime loans, many of which are doomed to fail."

Some minority customers, the story charges, are illegally steered to Vanderbilt Mortgage, a Clayton subsidiary, for loans that charge minority borrowers "substantially higher rates, on average, than their white counterparts" with similar incomes.

It also accuses Clayton of using Spanish to market its homes, but then having its language skills "disappear" as customers are rushed through signing documents in English, ending up with unexpectedly high interest rates and monthly payments, along with unforeseen fees and insurance.

Clayton's practices, the story says, are "part of a corporate culture that has condoned racism, including black employees fired while white workers used discriminatory slurs and kept their jobs, and phone collectors casually insulting borrowers with racist stereotypes."

A substantial markup, large fees and down payments, allow Clayton to "recoup more than half the wholesale price of the home in a year" so that even when loans go bad quickly it still makes money. In addition, Clayton can repossess and resell a home when buyers default, the story says.

Clayton has responded with an extensive news release that "categorically and adamantly" denies discriminating against customers or employees as it helps "families from all walks of life, including people in historically underserved markets, achieve the American dream of home ownership."

It accuses the story's authors, Dan Wagner and Mike Baker, of "activism masquerading as journalism."

Clayton says "race and ethnicity are never considered" for its loans and contends that when factors beyond income, such as credit scores, are included, rates for whites and nonwhites can be comparable.

Because "everyone loses" when a loan goes bad, and Clayton keeps most of its loans on its own books, the company says it makes sure all borrowers have the "reasonable ability" to pay it back. Clayton says it works hard to keep buyers in homes, including loan modifications in some instances. It says 97 percent of borrowers made their payments over the past 12 months.

In interviews with CNBC in early May, after the publication of the initial allegations against Clayton, Buffett said, "We are not forcing loans on anybody" and in three years with 300,000 loans, he has "not received one letter of complaint from anybody."

He added that the loan applications are written "very clearly," although some small number of borrowers may not understand what they were doing.

Buffett argued that while Clayton's foreclosure rates are relatively low, "Everybody has foreclosures. If you just helped the people that were absolutely certain to pay, like me, you wouldn't sell many homes and a lot of people would be denied a chance to get homes."

So far, the controversy hasn't affected the presidential race, but one writer thinks that could change.

Primarily citing the Clayton accusations, Salon contributing writer David Dayen calls Buffett a "phony" who is "cutthroat, not cuddly."

He concludes that either Democrats are so "desperate to have a billionaire validator" that they overlook the negatives of his "drive for profit," or they "sincerely believe in how Buffett earns his fortune. Either one isn't exactly flattering."

Berkshire has not yet responded to a request for comment on the Salon piece.