Stocks dropped on Monday after China escalated its trade battle with the U.S. by letting its currency sink to an 11-year low. The move prompted a rebuke from President Donald Trump, who in a post on Twitter accused the Chinese government of currency manipulation.

All three major stock indexes lost at least 2.5%. The Dow, which opened 400 points lower, lost 685 points, or 2.6%, by midday. It was trading falling to 25,798 as of 1:20 p.m. Eastern Time. The S&P 500 fell 2.5% to 2,857, while the Nasdaq fell 3% to 7,756.

The plummet is a response to the escalating trade war between the U.S. and China. After Mr. Trump last week announced surprise tariffs on $300 billion of Chinese imports, China responded by allowing the yuan’s exchange rate to sink below seven per dollar.

Dow drops 750 points, markets rattled after China lowers currency