Investors lulled into thinking U.S. regional banks were out of the woods after ruptures last year have been given a jolt by New York Community Bank. The under-the-radar lender's earnings report sparked a sell-off in regional bank shares in a warning for investors that had grown inured to the sector's sensitivity to high Federal Reserve interest rates nearly a year after two banks failed. While NYCB's confluence of problems are unique to its balance sheet, elements of its earnings underscored regional lenders' ongoing sensitivity to high Fed rates which continue to squeeze commercial real estate (CRE) portfolios and lending margins, investors said.