Nasdaq drops nearly 3%, Dow closes more than 300 points lower as tech rolls over

U.S. stocks closed sharply lower on Tuesday, erasing earlier gains, as a decline in the broader tech sector brought the major averages down.

The Nasdaq composite fell 2.9 percent as shares of Apple and Amazon declined. The S&P 500 pulled back 1.7 percent, with tech sliding 3.5 percent. The Dow Jo…