TOKYO, May 15 (Xinhua) -- Tokyo stocks were flat Tuesday morning as investors sold to lock in gains while others were encouraged to buy on the back of a comparatively weak yen.

The 225-issue Nikkei Stock Average edged down 3.07 points, or 0.01 percent, from Monday to 22,862.79.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, gained 3.22 points, or 0.18 percent, to 1,809.14.

Real estate, and pulp and paper issues comprised those that declined the most, while bank, and textile and apparel issues comprised those that gained the most by the morning break.