Stocks dropped across the board Friday with losses accelerating into the close after President Trump caught markets off guard by resuming his harsh tariff threats against China, a reprise of the bad old days of April when markets plunged on trade war headlines.

The Dow Jones industrial average dropped 1.9 percent, the S&P 500 lost 2.7 percent, and the Nasdaq was off a nasty 3.6 percent. US Treasury yields, oil prices and the dollar plunged on the tariff news.

President Trump posted on social media that China was hostile, that he would not meet with President Xi as scheduled in South Korea because of Xi's restrictions on rare earth sales to the US. Trump said he was preparing a massive increase of tariffs on Chinese products. The tariff comments appeared to reignite the US-China trade war that appeared in abeyance, and gave investors an excuse to take profits after a great run to record highs.

A shift in sentiment toward risk aversion on the trade news drew additional impetus from bad feeling around the 10th day of the US government shutdown and as an administration official said layoffs were under way.

Among sectors and stocks, worst hit were those with heavy China exposure, including AMD, Nvidia, and Tesla.

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