The Dow futures index plummeted shortly after President Trump’s announcement about levying $100 billion in additional tariffs on China.

The pre-market trading index fell more than 400 points Thursday night after the White House released a statement lambasting China for its unfair trade practices and warned of massive penalties.

“I have instructed the [US Trade Representative] to consider whether $100 billion of additional tariffs would be appropriate under section 301 and, if so, to identify the products upon which to impose such tariffs,” the statement from Trump read.

The futures index rebounded slightly after the free fall, but was down 368 points, or about 1.5 percent, as of 9 p.m.

The markets have been volatile in recent weeks due, in part, to fears of a trade war with the Asian nation.