Tokyo stocks plunged on Monday, with the Nikkei stock index shedding more than 4 percent at one point, as investors sought to lock in gains from recent sharp rises in heavyweight technology shares.The 225-issue Nikkei Stock Average ended down 2,563.52 points, or 3.85 percent, from Friday at 64,024.60. The broader Topix index finished 96.71 points, or 2.45 percent, lower at 3,852.38.On the top-tier Prime Market, the main decliners were nonferrous metal, electric appliance and glass and ceramics product issues.The U.S. dollar traded narrowly in the lower 160 yen range in Tokyo, supported by s…READ FULL ARTICLE