Thu, Feb 11, 2016, 10:05 AM EST - U.S. Markets close in 5 hrs 55 mins

Wall St. tumbles as investors run to safety

Federal Reserve Chair Janet Yellen on Wednesday acknowledged tightening financial conditions and uncertainty about China and the risks that posed to the U.S. economy, but still kept open the possibility of further interest rate hikes. The dollar hit a 16-month low against the yen and investors migrated to gold and top-rated bonds. Prices on fed fund futures, used to predict future policy rates by the Fed, surged…