Dow drops 653 points

U.S. stocks on Monday posted their worst Christmas Eve session ever, as a perfect storm of concerns drove investors to bail out of a market that was already badly bruised.

The blue-chip Dow Jones Industrial Average had its steepest drop on Christmas Eve in its 122-year history. It also was the worst Christmas Eve for the tech-heavy Nasdaq Composite and the first time the broader S&P 500 ever had more than a 1 percent drop on Dec. 24. The loss for the S&P 500 put the index into bear market, where it joined the Nasdaq.

If the markets had not closed at 1 p.m. ET for the holiday, the damage might have been worse.

A trifecta of concerns drove investors to sell: The prospect of rising interest rates; global economic weakness; and the likelihood that the partial government shutdown will extend into next year.