Wells Fargo informed investors Thursday that it just lost more than $328 million "as a result of credit events."

Barron's blogger Bob O'Brien takes the company to task this morning for its vague announcement:

"Thank goodness those banks have gotten religion on the issue of transparency, eh? As Wells Fargo (WFC) has shown us, banks talk to shareholders the way mobsters used to talk to prosecutors. It’s bankers practicing omerta -- the old custom of absolute silence."

The write-off changes the company's previously reported fourth-quarter loss from 79 cents to 84 cents per share.

A spokesperson told Barron's it wouldn't comment beyond the press release. Analysts suggested the charge might have come from another bank that Wells Fargo invests in.

O'Brien writes that without more transparency about the "credit errors," there is a risk that investors will be blind-sided in the future.