The U.S. dollar fell to the mid-160 yen level in Tokyo on Thursday after touching a 37-year high overnight, as repeated warnings by Japanese authorities strengthened fears of intervention. Market participants were increasingly cautious that the Japanese Finance Ministry could step in anytime to stem the yen’s slide after the U.S. currency soared to as high as 160.88 yen, its highest level since December 1986, in New York overnight, surpassing a recent high of 160.24 yen on April 29. At noon, the dollar fetched 160.45-46 yen compared with 160.78-88 yen in New York and 159.89-91 yen in Tokyo at …