The ETF is on pace for its fifth straight negative day with unusually heavy trading volume. Nearly 27 million shares have changed hands so far Tuesday, more than eight times its 30-day average volume.

Korea Electric Power’s American depositary receipts (ADRs) dropped 5%, and Korean e-commerce giant Coupang shed 6%. KT Corp., formerly Korea Telecom, saw shares fall 3%. Posco, a South Korean steel manufacturer, declined more than 6%.

Within three hours of Yoon declaring martial law late Tuesday night, 190 out of the 300 National Assembly lawmakers gathered to overturn the emergency order.

The president accused opposition parties of sympathizing with North Korea and controlling parliament. Yoon did not specify how martial law — a temporary rule by military authorities in a time of emergency — would affect governance and democracy in the country.

“The Administration is in contact with the ROK government and is monitoring the situation closely,” said the White House National Security Council in a statement to NBC News.

Under the martial law declaration, all political activities and acts that “incite social disorder” are prohibited. This is the first time since 1980 that a South Korean leader has issued a martial law declaration.

The Korea Exchange announced it would hold an emergency meeting “to prepare response measures” and  later decide whether the market would open on Wednesday, according to local media reports.

The U.S. dollar jumped 1.9% against the South Korean won Tuesday.