The Dow Jones Industrial Average was falling further in afternoon trading on Friday amid worries about escalating conflict in the Middle East.

The Dow was down 510 points, or 1.3%. The S&P 500 was down 1.5%. The Nasdaq Composite was down 1.7%.

The CBOE Volatility Index, or Vix, was up 25% to 18.67. That would be its highest close for the market’s fear gauge since Oct. 30, when it was at 19.75.

Ed Yardeni, president and chief investment strategist at Yardeni Research, points to reports the U.S. and Russia are working to avert a direct attack on Israel by Iran.

“The financial markets are bracing for this calamitous scenario,” Yardeni writes. “The S&P 500 has had a nearly vertical ascent of 27.6% from 4117.37 on October 27, 2023 to 5254.35 on March 29. That might be it for a while, especially if push does come to shove between Israel and Iran.”