Shares in the globally connected Swiss bank Credit Suisse plunged Wednesday and dragged down other major European lenders as fears about deeper problems in the world banking system spread in the wake of bank failures in the United States. At one point, Credit Suisse shares lost more than a quarter of their value, hitting a record low after the bank’s biggest shareholder – the Saudi National Bank – told news outlets that it would not inject more money into the bank, which was beset by problems long before the U.S. banks collapsed. The turmoil prompted an automatic pause in trading of Credit Suisse shares on the Swiss market and sent shares of other European banks tumbling, some by double digits. That fanned new fears about the health of financial institutions following the recent collapse of Silicon Valley Bank and Signature Bank in the US.