NEW YORK, March 5 (Xinhua) -- U.S. stocks opened lower on Monday as U.S. President Donald Trump's steep tariffs on steel and aluminum imports continued to rattle the market.

Shortly after the opening bell, the Dow Jones Industrial Average fell 122.04 points, or 0.50 percent, to 24,416.02. The S&P 500 decreased 11.49 points, or 0.43 percent, to 2,679.76. The Nasdaq Composite Index was down 24.05 points, or 0.33 percent, to 7,233.82.

Trump said on Thursday that he would impose 25 percent of tariff on steel imports products and 10 percent on aluminum as early as the following week.

Many observers fear that the planned tariffs would raise prospects of a trade war and hurt the U.S. economy.

U.S. stocks tumbled for a fourth straight session on Monday, with all three major indices dropping more than 1 percent.

Analysts said the recent sell-off reflected Wall Street's concerns over inflationary risks and economic slowdown, two threats that tariffs and other protectionist measures could bring.

Last week, all three major indices saw sharp decreases, with the Dow, the S&P 500 and the Nasdaq tumbling 3.0 percent, 2.0 percent and 1.1 percent, respectively. Enditem