U.S. stocks open lower amid geopolitical worries

U.S. stocks opened lower Wednesday as investors became cautious amid geopolitical concerns.

The White House has accused Russia of trying to cover up the suspected chemical weapon attack in Syria, though U.S. President Donald Trump has said the United States will not launch a ground war in the Mideast country, according to Market Watch.

In addition, the Trump administration is also navigating rising tensions with the Democratic People's Republic of Korea (DPRK).

On the economic front, U.S. import prices declined 0.2 percent in March, in line with market consensus, the Labor Department reported Wednesday. In contrast, the price index for U.S. exports increased 0.2 percent in March, after advancing 0.3 percent in February.

Meanwhile, investors also kept a close eye on the earnings season, as JPMorgan Chase, Citigroup and Wells Fargo are set to report later this week.

Shortly after the opening bell, the Dow Jones Industrial Average fell 34.03 points, or 0.16 percent, to 20,617.27. The S&P 500 lost 5.02 points, or 0.21 percent, to 2,348.76. The Nasdaq Composite Index decreased 7.46 points, or 0.13 percent, to 5,859.31.

On Tuesday, U.S. stocks ended mildly lower as investors meditated on the comments from Federal Reserve Chair Janet Yellen.

During an event at the University of Michigan on Monday, Yellen said the U.S. economy was "pretty healthy," thanks in part to the Fed's long-running stimulus campaign, which the central bank is moving to end. Endi