Stocks slumped on Friday, with the Dow taking a triple-digit dive and the Nasdaq losing nearly 2 percent, on market concerns over escalating tension in Ukraine.
The Dow Jones Industrial Average closed unofficially down 140 points, the S&P 500 lost 15 points and the Nasdaq shed 72 points, or 1.75 percent.
Geopolitical issues were on the minds of investors as Ukrainian forces reportedly killed up to five pro-Moscow rebels as Russian troops resumed military drills along that nation's border with Ukraine.
The United States and four European allies agreed that Russia had not lived up to the terms of the Ukraine peace accord, with the White House vowing a coordinated response to "impose costs" on Russia.
"A large percentage of S&P 500 earnings comes from overseas; if Europe does less well, it would have an impact," said Scott Wren, senior equity strategist at Wells Fargo Advisors. "Going into the weekend, what could happen? So people are squaring up and going home without hanging it out there too far.
"If Russia plays hard ball and cuts off the supply of natural gas to Europe, prices would go up for consumers and hurt consumer spending, and make the price of doing business more expensive. If there is less discretionary spending and less economic growth in Europe, it would hurt the growth of our companies doing business in Europe," Wren said.
Russian stocks were slammed, including software company Yandex, down 17 percent.
And Standard & Poor's cut its currency rating on Russia, as capital continues to flow out of the country amid heightened tensions with the West. S&P downgraded Russia's foreign currency rating to one notch above "junk" status at BBB-/A-3, down from BBB/A-2.
On the earnings front, Ford fell over 3 percent after the auto manufacturer reported earnings below expectations as a result of increasing warranty reserves in North America for older vehicles by $400 million. Amazon.com dropped nearly 10 percent after forecasting a loss in the current quarter.
Gold futures for June delivery climbed $10.20, or or 0.8 percent, to settle at $1,300.80 an ounce, leaving it 0.5 percent higher for the week; crude for June delivery fell $1.34 or 1.3 percent, to $100.60 a barrel.