Stocks fell again on Monday, following four straight weeks of declines, as investors grew increasingly concerned higher energy prices stemming from the Russia-Ukraine conflict would slow the economy while raising inflation.

The Dow Jones Industrial Average lost about 400 points, or 1.2%. The S&P 500 declined 1.3%, falling deeper into correction territory. The Nasdaq Composite was lost 1.6%, also in a technical correction.

As the Russia- Ukraine war continues, investors are monitoring the potential economic ramifications of disruptions in the global supply of energy.

“Consequently, ‘stagflation’ is rapidly becoming the central focus in portfolio strategies,” said Jim Paulsen, chief investment strategist for the Leuthold Group. “Preparing for slower growth and more persistent inflation is driving investor fears and actions.”

Overnight on Sunday, U.S. oil prices hit their highest level since 2008 amid an ongoing war between Russia and Ukraine. West Texas Intermediate crude futures, the U.S. oil benchmark hit $130 per barrel at one point before pulling back. WTI Crude is now up 1.5% around $117 per barrel. The international benchmark, Brent crude, spiked to to $139.13 per barrel — its highest since July 2008 — before pulling back to around $121.