Market Pulse: Dow falls 300 points and stock market stumbles as Russian troops sent to Ukraine

U.S. stock benchmarks on Tuesday morning opened solidly lower after Russian President Vladimir Putin sent troops into Ukraine, sparking concerns of an invasion of Kyiv. The Dow Jones Industrial Average DJIA fell 300 points, or 0.9%, to 33,784.The S&P 500 index SPX declined 27 points, or 0.6%, to reach 4,321.The Nasdaq Composite IndexCOMP was trading 0.8% lower at 13,439. On Tuesday, Russian forces entered Ukraine on a so-called peacekeeping mission. Western officials fear that Moscow is using support of a pro-Russian region of Ukraine as a pretext to launch an all-out assault on its neighbor, something Russia has denied.

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