CHARLOTTE, N.C. ( TheStreet) -- Bank of America ( BAC) Friday disclosed details of repurchase agreements that it incorrectly classified as sales, according to published media reports. The mistakes, which the bank acknowledged in a letter filed Friday with the Securities and Exchange Commission, effectively hid billions of dollars of debt, according to a report in The Wall Street Journal. The bank, which sent the letter to the SEC earlier this year, said the six transactions, made at the ends of quarters from 2007 to 2009, weren't material to its financial results or earnings, the report said. The classifications were for as much as $10.7 billion in repurchase agreements, or repos, the report added. > > Bull or Bear? Vote in Our Poll The disclosure comes as the SEC is preparing to report the results of an inquiry into how banks account for repo agreements, the report noted. In the letter, the bank said the incorrect accounting wasn't intentional. Bank of America first acknowledged the mistakes in its first-quarter earnings report, but the letter filed Friday reveals details of the transactions for the first time, the report said. The six transactions in question are called "dollar roll" trades, the report said. In them, the bank's investing-banking unit transferred mortgage-backed securities to an unidentified trading partner and simultaneously agreed to repurchase similar securities from the partner soon afterward, the report added. Bank of America said it has not conducted such transactions since early last year. The company's shares closed Friday up 25 cents at $15.11.