The Tokyo stock market ended sharply lower Monday, with the downtrend in share prices continuing unabated amid growing worries about the ailing economy.

Despite last week's announcement of a set of economic stimulus measures to be taken by the government, the benchmark 225-issue Nikkei average plunged 515.49 points, or 3.4 percent, to end the day at 14,799.40.

The key market gauge ended below the 15,000 level for the first time in 29 months. Growing pessimism over the prospects of economic recovery, along with fears about a growing number of business failures, sent Tokyo stocks into free fall, analysts said.