TOKYO, Oct. 5 (Xinhua) -- Tokyo stocks lost ground Friday morning following overnight losses on Wall Street due to a spike in long-term U.S. Treasury yields denting investor sentiment here.

The 225-issue Nikkei Stock Average edged down 190.98 points, or 0.8 percent, from Thursday to 23,784.64.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, lost 9.22 points, or 0.51 percent, at 1,791.97.

Chemical, nonferrous metal, and mining-linked issues comprised those that declined the most by the morning break.