WELLS Fargo chief executive John Stumpf has stepped down, as the US's second largest bank is mired in a scandal over sales practices. The bank said Mr Stumpf had retired effective immediately and quit as chairman. It had earlier said Mr Stumpf would forfeit $54 million in shares. Mr Stumpf faced congressional hearings and consumer wrath last month after the bank was found to have opened millions of accounts, without customers' permission, to reach aggressive sales targets. Senator Elizabeth Warren said he had shown "gutless leadership”.