Amazon stock plunged 8% in premarket trades Friday. The e-commerce giant reported second-quarter results that topped Wall Street's expectations, but gave a mixed outlook. For the current quarter, Amazon predicted sales of $176.75 billion at the midpoint of its range, compared with analyst expectations for $173.27 billion.

Markets are assessing the reshaped US trade landscape after Trump on Thursday laid out steep new tariffs for dozens of countries.

The Dow Jones Industrial Average dropped 542.40 points, or 1.23%, closing at 43,588.58. The S&P 500 shed 1.60% to end at 6,238.01, while the Nasdaq Composite dipped 2.24% and settled at 20,650.13.