A buying frenzy sent Tokyo share prices forging ahead in recent weeks, lifting the key Nikkei average back above the 11,000 level.

The market benchmark leaped roughly 20 percent in just a couple of weeks, a development rarely seen in recent years.

The Nikkei average of 225 leading stocks soared 638.22 points to end at 11,450.22 on March 4 and has since repeatedly reclaimed the 12,000 level on an intraday basis, a level unseen since early August.