Wall Street sinks 3% after Fed cites economic "risks"

NEW YORK (Reuters) - Stocks suffered their worst drop in a month after the Federal Reserve said there were "significant downside risks" to the economy even as it took another stab at boosting growth.

The Fed, as expected, said it would buy more long-term Treasury securities in an effort to lower borrowing rates. But investors worry that the Fed's latest plan will have little effect on lending in an economy that appears to be stagnating, which the Fed also noted.