Mortgage credit crunch roils markets

Countrywide, WaMu warn money for loans is drying up

The flight of investors away from securities backed by mortgage loans is affecting major lenders like Countrywide Financial and Washington Mutual, and sending shocks through financial markets despite efforts by central banks to ease the liquidity crunch by making billions in short-term loans available.

An announcement by the French bank BNP Paribas on Thursday that it was suspending three funds invested in securities backed by U.S. subprime loans sparked a stock sell-off and flight to safe investments like Treasurys.