Dow drops 450 points, S&P 500 slides more than 1.5% as Facebook drags tech stocks lower
Facebook was the worst-performing stock in the S&P 500, sliding 6.9 percent.
Shares of the social media giant fell after reports said political analytics firm Cambridge Analytica was able to collect data on 50 million people's profiles without their consent.
Investors also cast a wary eye at Washington following a Twitter tirade from Trump over the weekend.
Fred Imbert    | @foimbert