The Federal Reserve Bank of New York sold a multi-billion-dollar parcel of risky mortgage bonds on Thursday to a unit of Credit Suisse in its single-largest sale of troubled assets from the financial crisis.

The bonds were part of a portfolio that the New York Fed took on as part of the 2008 bailout of American International Group. The deal came after the regional Fed bank quietly solicited bids from four large securities dealers, and could set a precedent for how it disposes of other assets in the coming months, market participants said.