The US mortgage foreclosure crisis deepened as it emerged that Wells Fargo may have used practices that prompted rivals to halt home repossessions, and JPMorgan Chase said banks might be fined over the issue.

Bank of America, JPMorgan and GMAC have halted foreclosures after learning that "robo signers" had rubber-stamped thousands of mortgage documents without checking their accuracy. Attorneys-general in 50 states have launched a joint investigation into the matter.
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Jamie Dimon, JPMorgan chief executive, on Wednesday became the first top banking executive to say some attorneys-general may levy penalties on banks for their foreclosure practices.

Legal documents obtained by the Financial Times suggest that Wells Fargo, the second-largest US mortgage servicer, also used a "robo signer". Unlike its rivals, Wells Fargo has not halted foreclosures. The San Francisco-based bank said on Tuesday it was reviewing some pending cases, but it has maintained that it has checks and balances designed to prevent serious procedural lapses.

In a sworn deposition on March 9 seen by the FT, Xee Moua, identified in court documents as a vice-president of loan documentation for Wells, said she signed as many as 500 foreclosure-related papers a day on behalf of the bank.